RADIO COMMUNICATION METHOD AND RADIO COMMUNICATION APPARATUS
TECHNICAL FIELD
[0001] The embodiments discussed herein are related to a radio
communication method and a radio communication apparatus.
BACKGROUND ART
[0002] At present, portable telephone systems, radio MANs (Metropolitan
Area Networks), and other radio communication systems are in wide use. In
the field of radio communications, next-generation communication technologies
is continued to discuss to further improve communication speeds and capacities.
For example, in the 3GPP (3rd Generation Partnership Project), which is one of
the standards party, what is called LTE (Long Term Evolution) radio
communication system and LTE-A (Long Term Evolution-Advanced) radio
communication system which extend LTE, is proposed.
[0003] In such a radio communication system, a radio base station allocates
radio resource to terminal, performs scheduling by deciding encoding and
modulation method, and thereby attempts to perform radio communication
efficiently. The radio base station can decide on encoding and modulation
method according to the state of radio link, by performing scheduling using
information relating to channel state such as radio link quality.
[0004] There is a CSI (Channel State Information) as an information related
to channel state. For example, the CSI is an information relating to channel
state, and the terminal generates the CSI and reports to the radio base station.
Such the CSI reporting, there is periodic reporting in which the terminal reports
CSI periodically, and aperiodic reporting in which reporting is not periodic, for
example. In the case of periodic reporting, the terminal transmits the CSI to
the radio base station periodically with predetermined timing for example, and
in the case of aperiodic reporting, the terminal transmits the CSI with timing
that is not predetermined for example.
[0005] In the case of periodic reporting, the terminal transmit the CSI by
using a PUCCH (Physical Uplink Control CHannel). The PUCCH is a physical

channel for control signal transmission in an uplink (a link from the terminal to
the radio base station), for example. However, when the terminal transmits
data simultaneously with the CSI, the terminals multiplexes the CSI with data
and transmits the CSI by using a PUSCH (Physical Uplink Shared CHannel).
The PUSCH is a physical channel for data transmission in the uplink, for
example.
[0006] On the other hand, the terminal transmits the CSI using the PUSCH
in the case of aperiodic reporting . For example, even when the terminal does
not transmit data, the terminal transmits the CSI by using the PUSCH.
[0007] In the case of data transmission using the PUSCH, the radio base
station transmit a control signal (PDCCH signal) by using a PDCCH (Physical
Downlink Control CHannel) to the terminal, and the terminal transmits data by
the PUSCH by using the control signal transmitted as the PDCCH signal. The
PDCCH is a physical channel for control information transmission in a downlink
direction (the direction from the radio base station to the terminal), for example.
[0008] There is a DCI format 0 ((Downlink Control Information) format 0) as
one format for control signal transmitted by the PDCCH. FIG. 59 illustrates an
example of parameters included in the DCI format 0 for a case of frequency
division duplex (FDD) transmission. As illustrated in FIG. 59, one parameter
included in the DCI format 0 is "CQI request". The "CQI request" is a
parameter indicating whether the terminal performs CSI aperiodic reporting or
not, for example. For example, when the radio base station transmits "1" to
the terminal as the parameter value in the "CQI request" field, the terminal
performs CSI aperiodic reporting.
[0009] On the other hand, it also studied that radio communication is
performed by using a plurality of frequency bands in parallel in the radio
communication system. Each of the plurality of frequency bands is called a
component carrier (hereafter "CC") for example, and large-capacity radio
communications can be performed by using a plurality of CCs (or a plurality of
frequency bands).
[0010] Regarding CSI reporting in such the radio communication system
using the plurality of frequency bands, for example there is a following

technique. That is, there is a technique in which, when the radio base station
uses one frequency band of a plurality of frequency bands in the downlink
direction to transmit control signal, the terminal performs CSI reporting for the
frequency band. In this case, for example, when the radio base station
transmit the control signal of a DCI format 0 by using DLCC#1 in the downlink
direction (the first downlink CC), the terminal may perform CSI reporting for the
DLCC#1.
[0011] Further, there is another technique in which, when the radio base
station transmits the control information by using one of the plurality of
frequency bands in the downlink direction, the terminal may perform CSI
reporting for all of the plurality of downlink-direction frequency bands.
[0012] Non-patent Reference 1: 3GPP TS 36.212V9.1.0 (for example,
section 5.3.3.1)
Non-patent Reference 2: 3GPP TS 36.213V9.1.0 (for example, sections
7.2.1 and 7.2.2)
Non-patent Reference 3: "CQI/PMI/RI reporting for carrier aggregation",
3GPP, R1-103090
Non-patent Reference 4: "Aperiodic CQI Reporting for Carrier
Aggregation", 3GPP, R1-102868
SUMMARY OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0013] However, when the terminal performs CSI reporting for the
frequency band used in control signal transmission, the terminal cannot report
the CSI for the frequency band not used in control signal transmission, of the
plurality of downlink-direction frequency bands. Hence using this technique,
the radio base station cannot cause the terminal to transmit the CSI for an
arbitrary frequency band of the plurality of frequency bands.
[0014] On the other hand, when the terminal performs CSI reporting for all
frequency bands of the plurality of downlink-direction frequency bands, the
radio base station can receive the CSI for all the downlink-direction frequency
bands. However, there are also cases in which the radio base station uses only
the CSI for a number of frequency bands among the received CSI reports. In

such a case, because the CSI for all frequency bands is transmitted from the
terminal to the radio base station, transmissions of frequency band CSIs which
are not used are wasteful, and throughput cannot be improved.
[0015] Accordingly, it is an object in one aspect of the invention to provide
a radio communication method and radio communication apparatus such that
information relating to a channel state in an arbitrary frequency bandwidth
among a plurality of frequency bandwidths can be reported.
[0016] Furthermore, it is an another object in one aspect of the invention to
a radio communication method and radio communication apparatus such that
throughput can be improved.
MEANS FOR SOLVING THE PROBLEM
[0017] According to an aspect of the embodiments, a radio communication
method for performing radio communication by using a plurality of frequency
bands in a first radio communication apparatus and a second radio
communication, the method including transmitting to the second radio
communication apparatus a first channel state information request
corresponding to each of the plurality of frequency band, by the first radio
communication apparatus; and transmitting to the first radio communication
apparatus an information relating to a channel state for the frequency band
specified by the first channel state information request, when the second radio
communication apparatus receives the first channel state information request,
by the second radio communication apparatus.
EFFECTIVENESS OF THE INVENTION
[0018] A radio communication method, radio communication system and
radio communication apparatus can be provided such that, information relating
to channel states in an arbitrary frequency band of a plurality of frequency
bands can be reported, Further, a radio communication method and radio
communication apparatus can be provided such that throughput can be
improved.
BRIEF DESCRIPTION OF DRAWINGS
[0019] FIG. 1 illustrates an example of the configuration of a radio
communication system;

FIG. 2 illustrates an example of the configuration of a radio communication
system;
FIG. 3 illustrates an example of component carrier setting;
FIG. 4 illustrates an example of the configuration of a radio frame;
FIG. 5 illustrates an example of PDCCH and other setting;
FIG. 6 illustrates an example of DCI format parameter;
FIG. 7A illustrates an example of a DLCC for CSI report; and FIG. 7B
illustrates an example of a DLCC for CSI report;
FIG. 8 illustrates an example of the configuration of a base station;
FIG. 9 illustrates an example of the configuration of a terminal;
FIG. 10 is a flowchart illustrating an operation example;
FIG. 11 is a flowchart illustrating an operation example;
FIG. 12 illustrates an example of DCI format parameter;
FIG. 13 illustrates an example of PDCCH and other setting;
FIG. 14 illustrates an example of the configuration of a base station;
FIG. 15 illustrates an example of the configuration of a terminal;
FIG. 16 is a flowchart illustrating an operation example;
FIG. 17 is a flowchart illustrating an operation example;
FIG. 18A illustrates an example of DCI format parameter; and FIG. 18B
illustrates an example of DCI format parameter;
FIG. 19A illustrates an example of PDCCH and other setting; and FIG. 19B
illustrates an example of PDCCH and other setting;
FIG. 20 is a flowchart illustrating an operation example;
FIG. 21 is a flowchart illustrating an operation example;
FIG. 22A illustrates an example of a correspondence relation; and FIG. 22B
illustrates an example of a DLCC for CSI report;
FIG. 23 illustrates an example of the configuration of a base station;
FIG. 24 illustrates an example of the configuration of a terminal;
FIG. 25 is a flowchart illustrating an operation example;
FIG. 26 is a flowchart illustrating an operation example;
FIG. 27 illustrates an example of a correspondence relation;

FIG. 28A illustrates an example of a correspondence relation; and FIG. 28B
illustrates an example of a DLCC for CSI report;
FIG. 29 is a flowchart illustrating an operation example;
FIG. 30 is a flowchart illustrating an operation example;
FIG. 31A and FIG. 31B illustrate examples of a correspondence relation; and
FIG. 31C illustrates an example of a DLCC for CSI report;
FIG. 32 is a flowchart illustrating an operation example;
FIG. 33 is a flowchart illustrating an operation example;
FIG. 34 illustrates an example of a DCI format;
FIG. 35 illustrates an example of a DLCC for CSI report;
FIG. 36 is a flowchart illustrating an operation example;
FIG. 37 is a flowchart illustrating an operation example;
FIG. 38A illustrates an example of a DLCC for CSI report; and FIG. 38B
illustrates an ULCC for transmission;
FIG. 39 is a flowchart illustrating an operation example;
FIG. 40 is a flowchart illustrating an operation example;
FIG. 41 illustrates an example of a DLCC for CSI report;
FIGs. 42A-42C illustrate examples of a DLCC for CSI report;
FIG. 42C illustrates an example of a DLCC for CSI report;
FIG. 43 is a flowchart illustrating an operation example;
FIG. 44 is a flowchart illustrating an operation example;
FIGs. 45A-45E illustrates examples of a DLCC for CSI report;
FIG. 46 is a flowchart illustrating an operation example;
FIG. 47 is a flowchart illustrating an operation example;
FIGs. 48A-48C illustrates examples of CSI report timing;
FIG. 49 illustrates an example of a DLCC for CSI report;
FIG. 50 is a flowchart illustrating an operation example;
FIGs. 51A-51B illustrates examplse of a DLCC for CSI report;
FIG. 52 is a flowchart illustrating an operation example;
FIG. 53 is a flowchart illustrating an operation example;
FIG. 54A illustrates an example of a DCI format example; and FIG. 54B
illustrates an example of PDCCH and other setting;

FIG. 55 illustrates an example of the configuration of a base station;
FIG. 56 illustrates an example of the configuration of a terminal;
FIG. 57 is a flowchart illustrating an operation example;
FIG. 58 is a flowchart illustrating an operation example; and
FIG. 59 illustrates an example of a DCI format.
BEST MODE FOR CARRYING OUT THE INVENTION
[0020] Below, embodiments are explained in detail, referring to the
drawings.
[0021] First Embodiment
FIG. 1 illustrates an example of a configuration of a radio communication
system of a first embodiment. The radio communication system includes a first
radio communication apparatus 10 and a second radio communication
apparatus 20. The first radio communication apparatus 10 and second radio
communication apparatus 20 perform radio communications by using a plurality
of radio communication bands.
[0022] The first radio communication apparatus 10 includes a transmission
unit 11 and a reception unit 12.
[0023] The transmission unit 11 transmits first channel state information
requests, corresponding to each of the plurality of frequency band, to the
second radio communication apparatus 20.
[0024] The reception unit 12 receives information from the second radio
communication apparatus 20 relating to channel states for frequency bands
specified by first channel state information requests.
[0025] On the other hand, the second radio communication apparatus 20
includes a reception unit 21 and a transmission unit 22.
[0026] The reception unit 21 receives first channel state information
requests from the first radio communication apparatus.
[0027] The transmission unit 22 transmits information to the first radio
communication apparatus 10 relating to channel states for frequency bands
specified by first channel state information requests.
[0028] The first radio communication apparatus 10 transmits first channel
state information requests corresponding to each of the plurality of frequency

bands to the second radio communication apparatus 20, and the second radio
communication apparatus 20 transmits information relating to channel states
for frequency bands specified by the first channel state information requests to
the first radio communication apparatus 20.
[0029] Hence, of the plurality of frequency band, the first radio
communication apparatus 10 can receive from the first radio communication
apparatus 20 information relating to the channel state of an arbitrary frequency
band. Further, the second radio communication apparatus 20 transmits
information relating to the channel states for the specified frequency band, so
that compared with a case in which information relating to the channel states
for all frequency bands is transmitted, the radio resources required for channel
state reports is reduced, and to this extent the radio resources which can be
used in other data transmission are increased, so that throughput can be
improved.
[0030] Second Embodiment
FIG. 2 illustrates an example of the configuration of the radio communication
system of a second embodiment. The radio communication system includes a
radio base station apparatus (hereafter "base station") 100, and terminal
apparatuses (hereafter "terminals") 200 and 200a.
[0031] The base station 100 is a radio communication apparatus which
performs radio communication with the terminals 200 and 200a. The base
station 100 is connected to a wire higher-level network, and transfers data
signal (hereafter "data") between the higher-level network and the terminals
200 and 200a. The base station 100 ran use a plurality of (for example, five)
frequency band, called component carriers (CCs), in radio communication. The
base station 100 performs radio communication by using a portion of or all of
the plurality of frequency bands. Using the plurality of frequency bands to
perform radio communication, there is a case called "carrier aggregation".
[0032] The terminals 200 and 200a are radio communication apparatuses
which are radio-connected to the base station 100 and perform radio
communication, and may be, for example, portable telephone sets, portable
information terminal apparatuses, or similar. The terminals 200 and 200a

receive data from the base station 100, and transmit data to the base station
100. In this Description, the direction from the base station 100 to the
terminals 200 and 200a is called the "downlink" (DL) direction, and the direction
from the terminals 200 and 200a to the base station 100 is called the "uplink"
(UL) direction.
[0033] The base station 100 is one example of the first radio communication
apparatus 10 in the first embodiment, and the terminals 200 and 200a are
examples of the second radio communication apparatus 20 in the first
embodiment.
[0034] In the example of FIG. 2, an example of two terminals 200 and 200a
is illustrated, but there may be three or more terminals. The two terminals 200
and 200a may both have the same configuration, and unless stipulated
otherwise, the explanations are for the example of the terminal 200.
[0035] FIG. 3 illustrates an example of component carrier setting. When
FDD is used in radio communications between the base station 100 and the
terminal 200, for example five frequency bands, CC#1 to CC#5, are secured for
each of DL and UL. When referring simply to a "CC", this may mean a
combination of a frequency band for DL and a frequency band for UL. Further,
when TDD (Time Division Duplex) is used in radio communications, for example
five frequency bands are secured, without discriminating between those for DL
and for UL. FIG. 3 illustrates the FDD case. Here an example is illustrated for a
case in which the numbers of CCs are the same for DL and for UL, but cases
are also possible in which the numbers of CCs for DL and for UL are not equal.
[0036] The base station 100 sets bandwidths of each of CC#1 to CC#5,
taking into consideration the number of terminals planned for accommodation,
communication speed and similar. As examples of the bandwidths of each of
CC#1 to CC#5, for example 1.4 MHz, 5 MHz, 10 MHz, 15 MHz, 20 MHz, or
similar are possible. The base station 100 may set all of CC#1 to CC#5 to the
same frequency bandwidth, or may use different frequency bandwidths.
Further, the base station 100 may perform radio communication by using an
arbitrary number of CCs.

[0037] FIG. 4 illustrates an example of the configuration of a radio frame.
Radio frames are transmitted and received between the base station 100 and
terminal 200 in each CC. One radio frame includes a plurality of subframes (for
example, 10 subframes).
[0038] A minimum unit of the radio frame in the frequency direction is a
subcarrier, and the minimum unit in the time direction is a symbol. As multiple
access method, for example, for UL subframe SC-FDMA (Single Carrier-
Frequency Division Multiple Access), and for DL subframe, OFDMA (Orthogonal
Frequency Division Multiple Access), are used.
[0039] The UL subframe includes an area (or radio resource) for an uplink
physical shared channel (PUSCH). The PUSCH is a physical channel used for
example by the base station 100 to transmit user data and control information.
The base station 100 can allocate UL subframe to each terminal 200, and can
set the PUSCH for a plurality of terminals 200 and 200a in one UL subframe.
[0040] The DL subframe includes areas (or radio resources) for a downlink
physical control channel (PDCCH) and a downlink physical shared channel
(PDSCH, Physical Downlink Shared CHannel). The PDCCH area is set for N
symbols from the beginning of the DL subframe, and the PDSCH area is set for
the remaining symbols continuing from the PDCCH.
[0041] The PDCCH is a physical channel used by the base station 100 to
transmit L1/L2 (Layer 1/Layer 2) control signals to a terminal 200. Control
signals (PDCCH signals) transmitted in the PDCCH include control signals
relating to the PDSCH and PUSCH. PDCCH signals in the DCI format 0,
described below, are an example of control signals relating for example to the
PUSCH. Information indicated by control signals relating to the PUSCH includes,
for example, information indicating radio resources, information specifying the
data format such as modulation and encoding method (MCS: Modulation and
Coding Scheme), information relating to uplink retransmission control by HARQ
(Hybrid Automatic Repeat reQuest), and similar. Information indicated by
control signals relating to the PDSCH includes, for example, information
indicating PDSCH radio resource, information indicating the data format,
information relating to downlink retransmission control, and similar. The

terminal 200 can extract control signals relating to the PUSCH and PDSCH by
monitoring the PDCCH area of a CC in which there is the possibility that control
signals addressed to itself are transmitted.
[0042] FIG. 5 illustrates an example of PDCCH, PDSCH and PUSCH settings.
In this example, the base station 100 sets DLCC#1 and DLCC#3 as PDCCHs of
the five DL (downlink-direction) CCs, CC#1 to CC#5. For example, the terminal
200 can receive PDCCH signals from the base station 100 in DLCC#1 and
DLCC#3. In the PDCCH area of DLCC#1, a control signal indicating that the
terminal performs transmission of data and similar in ULCC#1, and a control
signal indicating that the terminal performs transmission of data and similar in
ULCC#2, are set. Further, a control signal indicating that DLCC#1 is used to
perform data reception, and a control signal indicating that DLCC#2 is used to
perform data reception, are set.
[0043] In this way, in the PDCCH area, the base station 100 can transmit
control signal relating to the physical channel CC different from the CC to which
the PDCCH belongs. Such scheduling, there is a case called "cross-carrier
scheduling". On the other hand, there is also scheduling called "same-carrier
scheduling". Same-carrier scheduling is a scheduling in which, for example, the
ULCC with the same number as the DLCC to which the PDCCH belong is used
to transmit data and similar.
[0044] On the other hand, the base station 100 can set each of the states of
CC#1 to CC#5 for each terminal 200. The terminal 200 performs radio
reception processing for each CC based on the states of CC#1 to CC#5. The
states of the CC can for example be classified into a "configured but deactivated
CC", a "configured and activated CC", and a "PDCCH monitoring set".
[0045] The "configured but deactivated CC" is for example a CC in a state
which is not currently used for data transmission, but which can be used
(inactive state). The terminal 200 need not monitor the PDCCH or PDSCH for
the inactive state DLCC. In the example of FIG. 5, DCLL#5 is in the inactive
state, and the terminal 200 may halt reception processing of the radio
frequency bandwidth.

[0046] The "configured and activated CC" is for example a CC in a state
which is currently used for data communication (active state). In the example
of FIG. 5, DLCC#1 to #4 are in the active state, and the terminal 200 perform
reception processing for the self-addressed PDSCH at least in these frequency
bandwidths.
[0047] The "PDCCH monitoring set" is for example an active state, and is
the set of CCs for which PDCCHs addressed to the terminal 200 can be set. In
the example of FIG. 5, this set includes the DLCC#1 and the DLCC#3. The
terminal 200 monitors the PDCCH in this radio frequency band. "PDCCH
monitoring set" can be defined as a subset of the "configured and activated
CCs" subset, but there are cases in which the terminal 200 perform PDCCH
reception processing in all the "configured and activated CCs". In this case,
"PDCCH monitoring set" and "configured and activated CC" are taken to mean
the same aggregate.
[0048] FIG. 6 illustrates an example of DCI format 0 parameter. As
described above, the DCI format 0 control signal is transmitted in the PDCCH
area from the base station 100 to the terminal 200, and include a control
information for transmission of data and similar in the uplink. In the first
embodiment, of the DCI format 0 parameters, "CQI request" (or a channel
state information request) has 5 bits for example, and using these 5 bits, CCs
for which CCI reports are to be made are specified, of the DLCC#1 to #5.
[0049] FIG. 7A illustrates an example of the relation between bits specified
by "CQI request" and CC for which CSI report are to be made. When the base
station 100 transmits "11100" as the "CQI request", the terminal 200 performs
CSI reports for the CCs DLCC#1 to #3. In this way, the parameter value
specified as the "CQI request" can specify not only one DLCC, but a
combination of a plurality of DLCCs.
[0050] In cross-carrier scheduling, the terminal 200 transmits CSI using an
ULCC specified by the "carrier indicator" of the DCI format 0.
[0051] In this way, the base station 100 can use the 5-bit "CQI request" to
specify arbitrary DLCC and cause CSI report to be made, and in this way, can
receive CSI for arbitrary DLCC from the terminal 200.

[0052] The number of bits in the "CQI request" may be other than 5 bits,
and for example 8 bits or similar can be used, according to the number of
DLCCs.
[0053] An example is explained of the DCI format 0 as the DCI format
including "CQI request" as the parameter; but any format may be used, so long
as the control signal format includes "CQI request".
[0054] Further, when the base station 100 uses the "CQI request" to specify
the CSI for which the CSI report is to be made, and the terminal 200 generates
and transmits to the base station 100 the CSI for the specified DLCC, this report
is for example an "aperiodic" CSI report. In the case of a periodic report,
report is periodically generated and transmitted by the terminal 200 for a DLCC
initially set or similar by the base station 100; in such a state, when the base
station 100 specifies the DLCC and causes CSI report to be made, the report is
for example "aperiodic".
[0055] The above is similarly true for the embodiments below which include
the second embodiment.
[0056] FIG. 8 illustrates an example of the configuration of the base station
100 in the second embodiment. The base station 100 includes a scheduler 110,
RS generation unit 112, PDCCH generation unit 113, PDSCH generation unit
114, multiplexing unit 115, radio transmission unit 116, antenna 120, radio
reception unit 130, first separation unit 131, PUCCH processing unit 132,
PUSCH processing unit 133, and second separation unit 134. The scheduler
110 inclueds a report CC decision unit 111.
[0057] The scheduler 110, report CC decision unit 111, RS generation unit
112, PDCCH generation unit 113, PDSCH generation unit 114, multiplexing unit
115, and radio transmission unit 116 correspond for example to the
transmission unit 11 in the first embodiment. The radio reception unit 130, first
separation unit 131, PUCCH processing unit 132, PUSCH processing unit 133,
and second separation unit 134 correspond for example to the reception unit 12
in the first embodiment.
[0058] The scheduler 110 manages allocation of DL radio resource and UL
radio resource. That is, when user data addressed to the terminal 200 arrives

in the buffer of the base station 100, the scheduler 110 allocates the DL radio
resource to the terminal 200. Further, the scheduler 110 detects the quantity
of user data that the terminal 200 is to transmit from control information
acquired from the PUSCH processing unit 133, for example, and allocates the
UL radio resource to the terminal 200. The scheduler 110 outputs the
scheduling result to the PDCCH generation unit 113.
[0059] The report CC decision unit 111 decides the DLCC for which there is
to be CSI report from the plurality of DLCCs. The scheduler 110 creates DCI
format 0 control information in which the corresponding bit in the "CQI request"
is set to "1" to generate a report for the DLCC thus decided, and outputs the
control information to the PDCCH generation unit 113.
[0060] The RS generation unit 112 generates and outputs to the
multiplexing unit 115 a reference signal (RS). The reference signal is a signal
used when a terminal 200 generates CSI, for example.
[0061] The PDCCH generation unit 113 generates control information for
downlink data (or control information relating to the PDSCH) based on the
scheduling result. The PDCCH generation unit 113 generates control
information for uplink data (or control information related to the PUSCH) based
on the scheduling results and DCI format 0 control information. The PDCCH
generation unit 113 performs error correction encoding of the generated control
information, and generates and outputs to the multiplexing unit 115 a PDCCH
signal.
[0062] The PDSCH generation unit 114 reads user data stored in a buffer
and addressed to the terminal 200, performs error correction encoding of the
read-out user data, and generates and outputs to the multiplexing unit 115 a
PDSCH signal.
[0063] The multiplexing unit 115 multiplexes the reference signal, the
PDCCH signal (control signal), and the PDSCH signal (data signal). The
multiplexing unit 115 outputs the multiplexed reference signal and similar to the
radio transmission unit 116.

[0064] The radio transmission unit 116 up-converts the multiplexed signal to
a radio signal by frequency conversion and similar, and outputs the signal to
the antenna 120.
[0065] The antenna 120 performs radio transmission to the terminal 200
radio signal output from the radio transmission unit 116. The antenna 120
receives radio signal transmitted from the terminal 200, and outputs the signal
to the radio reception unit 130. In the example illustrated in FIG. 8, there is
one antenna 120, used for both transmission and reception; however, a
plurality of antennas may be used separately for transmission and for reception.
[0066] The radio reception unit 130 down-converts radio signal received by
the antenna 120 by frequency conversion and similar, converts the radio signal
into baseband signal, and outputs to the first separation unit 131.
[0067] The first separation unit 131 extracts the PUCCH signal and PUSCH
signal from the baseband signal, outputs the PUCCH signal to the PUCCH
processing unit 132, and outputs the PUSCH signal to the PUSCH processing
unit 133. For example, the first separation unit 131 references the UL radio
resource of which the base station 100 notified to the terminal 200 by the
PDCCH, and extracts the PUCCH signal or PUSCH signal.
[0068] The PUCCH processing unit 132 performs error correction decoding
of PUCCH signal, and extracts control information relating to the PUCCH from
PUCCH signal. For example, the PUCCH processing unit 132 performs error
correction decoding and other processing corresponding to the encoding
method stipulated in advance between the base station 100 and the terminal
200.
[0069] The PUSCH processing unit 133 performs error correction decoding
of PUSCH signal, extracts user data and CSI from PUSCH signal, and outputs
the user data and CSI to the second separation unit 134.
[0070] The second separation unit 134 separates and outputs user data and
CSI.
[0071] FIG. 9 illustrates an example of the configuration of the terminal 200.
The terminal 200 includes an antenna 210, radio reception unit 220, separation
unit 221, measurement unit 222, CSI generation unit 224, PDCCH processing

unit 223, PDSCH processing unit 225, ACK/NACK generation unit 226, CSI
processing unit 227, user data processing unit 228, PUSCH generation unit 229,
PUCCH generation unit 230, multiplexing unit 231, and radio transmission unit
232. The terminal 200a is configured similarly to the terminal 200.
[0072] The radio reception unit 220, separation unit 221, PDCCH processing
unit 223, and PDSCH processing unit 225 correspond for example to the
reception unit 21 in the first embodiment. The CSI generation unit 224, CSI
processing unit 227, user data processing unit 228, PUSCH generation unit 229,
PUCCH generation unit 230, multiplexing unit 231 and radio transmission unit
232 correspond for example to the transmission unit 22 in the first embodiment.
[0073] The antenna 210 receives radio signal transmitted from the base
station 100 and outputs the radio signal to the radio reception unit 220. The
antenna 210 also transmits radio signal output from the radio transmission unit
232 to the base station 100. In the example illustrated in FIG. 9, one antenna
210 is used for both transmission and reception, however a plurality of
antennas may be used separately for transmission and for reception.
[0074] The radio reception unit 220 down-converts radio signal by
frequency conversion and similar, converting radio signal into baseband signal,
and outputs the converted baseband signal to the separation unit 221.
[0075] The separation unit 221 extracts RS signal, PDCCH signal, and
PDSCH signal from baseband signal, and outputs RS signal to the measurement
unit 222, outputs PDCCH signal to the PDCCH processing unit 223, and outputs
PDSCH signal to the PDSCH processing unit 225. For example, the separation
unit 221 receives transmitted signal by a PCFICH (Physical Control Format
Indicator CHannel). The PCFICH includes information indicating for example
the number of symbols (1, 2 or 3) to which PDCCH signal is mapped, and the
separation unit 221 can separate PDCCH signal by removing the number of
symbols from the beginning of DL subframe. The separation unit 221 can then
extract the PDSCH signal from the remaining symbols following the PDCCH
signal. Because for example the RS signal is disposed in a predetermined radio
resource, the separation unit 221 can use resource information held in advance
to separate the RS signal from the baseband signal.

[0076] The measurement unit 222 measures downlink channel reception
quality and other parameters of the channel state based on the RS signal
output from the separation unit 221, and outputs measurement value to the
CSI generation unit 224. At this time, the measurement unit 222 also outputs
information indicating for which DLCC, of a plurality of DLCCs, the
measurement values is made. For example, the measurement unit 222 holds,
as setting information, information indicating to which frequency bands DLCC#1
to CC#5 belong. Based on the setting information, the measurement unit 222
can then output information indicating for which DLCC measurement is made,
from the reception frequency band of the measured RS signal.
[0077] The PDCCH processing unit 223 performs error correction decoding
of PDCCH signal output from the separation unit 221 which may be addressed
to itself, and extracts control signal addressed to itself. As explained above, the
information indicated by control signal includes control information relating to
the PDSCH, and the control information relating to the PUSCH. The Control
information relating to the PUSCH (for example DCI format 0) includes for
example the "CQI request" specifying CC for which CSI report is to be made.
From the extracted control signal, the PDCCH processing unit 223 outputs to
the PDSCH processing unit 225 the control information relating to the PDSCH,
and outputs to the user data processing unit 228 the control information
relating to the PUSCH. The PDCCH processing unit 223 outputs the extracted
"CQI request" to the CSI generation unit 224.
[0078] The CSI generation unit 224 generates CSI for DLCC indicated by the
"CQI request" of the measurement values measured by the measurement unit
222. For example, the CSI generation unit 224 takes as input measurement
value from the measurement unit 222 and information indicating which DLCC
the channel states describe; of these, the CSI is generated for the channel state
of the DLCC indicated by the "CQI request" and is output to the CSI processing
unit 227.
[0079] The CSI may for example include a CQI (Channel Quality Indicator),
PMI (Precoding Matrix Indicator), RI (Rank Indicator), and similar. The CSI
generation unit 224 outputs as the CSI any of these, or a combination thereof.

The CQI is information indicating the reception quality of a radio channel, for
example (in this example, a downlink radio channel), and the PMI is an index
associated with a preceding matrix used for example by the base station 100.
The RI is for example the maximum number of streams which can be
transmitted in parallel.
[0080] The CSI generation unit 224 periodically generates a CSI for DLCC
other than specified DLCC, and outputs the generated CSI to the PUCCH
generation unit 230.
[0081] The PDSCH processing unit 225 references control information
relating to the PDSCH output from the PDCCH processing unit 223, and
performs error correction decoding of the PDSCH signal. By this means, user
data and similar transmitted from the base station 100 and addressed to the
terminal 200 is extracted. Further, the PDSCH processing unit 225 outputs a
signal indicating whether the PDSCH signal is received normally (or whether
user data or similar is extracted normally, or similar) to the ACK/NACK
generation unit 226.
[0082] Upon input of the signal from the PDSCH processing unit 225
indicating that the PDSCH signal is received normally, the ACK/NACK generation
unit 226 generates an ACK signal, and upon input of a signal indicating that a
PDSCH signal is not received normally, the ACK/NACK generation unit 226
generates a NACK signal. The ACK/NACK generation unit 226 outputs the
generated ACK signal or NACK signal to the PUCCH generation unit 230.
[0083] The CSI processing unit 227 performs error correction encoding and
similar of the CSI output from the CSI generation unit 224, and outputs the
result to the PUSCH generation unit 229.
[0084] The user data processing unit 228 references control information
relating to the PUSCH output from the PDCCH processing unit 223, performs
error correction encoding, modulation and other processing of the user data,
and outputs the result to the PUSCH generation unit 229.
[0085] The PUSCH generation unit 229 references control information
relating to the PUSCH output from the PDCCH processing unit 223, and outputs,
as PUSCH signal to be transmitted using the PUSCH, each of the output signals

from the CSI processing unit 227, the user data processing unit 228, and the
ACK/NACK generation unit 226. The PUSCH generation unit 229 outputs
PUSCH signal to the multiplexing unit 231.
[0086] The PUCCH generation unit 230 inputs the output from the
ACK/NACK generation unit 226 and the CSI output from the CSI generation unit
224 which is to be reported periodically, and outputs these as the PUCCH signal
to be transmitted using the PUCCH. The PUCCH generation unit 230 outputs
the PUCCH signal to the multiplexing unit 231.
[0087] The multiplexing unit 231 multiplexes the PUSCH signal and PUCCH
signal, and outputs the result to the radio transmission unit 232.
[0088] The radio transmission unit 232 performs frequency conversion and
other processing to up-convert the multiplexed PUSCH signal and PUCCH signal
to the radio signal, which is output to the antenna 210.
[0089] Next, an example of operation of the second embodiment is
explained. FIG. 10 and FIG. 11 are flowcharts illustrating an example of
operation. Below, the operation example illustrated in FIG. 10 and FIG. 11 is
explained in the order of the step numbers.
[0090] Firstly, the base station 100 decides on startup of aperiodic CSI
reporting, and decides for which DL CC CSI reports is to be made (S10, Sll).
For example, the base station 100 starts aperiodic CSI reporting when for
example a large quantity of downlink data is arrived, or when some other
condition is satisfied, and the report CC decision unit 111 decides for which CCs
CSI reports is to be made.
[0091] Next, the base station 100 generates "CQI request" bit according to
the DC CC for which CSI report is to be made (S12). For example, when the
report CC decision unit 111 causes CSI report to be made for the DLCCs from
DLCC#1 to #3, the scheduler 110 generates the "CQI request" bits "11100".
[0092] Next, the base station 100 generates the control information for
uplink data (S13). For example, the scheduler 110 generates the control
information for uplink data (for example DCI format 0 control information)
including the generated "CQI request" bits.

[0093] Next, the base station 100 generates the PDCCH signal (S14). For
example, the PDCCH generation unit 113 generates the PDCCH signal (control
signal) from control information for uplink data generated by the scheduler 110.
[0094] Next, the base station 100 transmits the PDCCH signal to the
terminal 200 (S15). For example, the radio transmission unit 116 converts to
the radio signal and transmits the PDCCH signal generated by the PDCCH
generation unit 113.
[0095] Next, the terminal 200 performs terminal-side processing (S16). FIG.
11 is a flowchart illustrating an example of operation for terminal-side
processing.
[0096] The terminal 200 receives the PDCCH signal (S161). For example,
the separation unit 221 separates the PDCCH signal and outputs the PDCCH
signal to the PDCCH processing unit 223, and the PDCCH processing unit 223
retrieves control information for downlink data (control information relating to
the PDSCH) and uplink data control information (control information relating to
the PUSCH) from the PDCCH signal.
[0097] Next, the terminal 200 determines whether the PDCCH signal
includes, as control information, control information for downlink data (S162).
There is also case in which the PDCCH signal includes, as control information
for downlink data, control information related to the PDSCH. On the other
hand, the signal length of the PDCCH signal is different for control information
relating to the PUSCH and for control information relating to the PDSCH. For
example, the PDCCH processing unit 223 can judge from the signal length of
the PDCCH signal whether control information related to the PDSCH is included.
Or, a Flag for format 0/format 1A differentiation included in the PDCCH signal
can be used to discriminate between control information relating to the PDSCH
and control information relating to the PUSCH.
[0098] Upon determining that the PDCCH signal includes the control
information for downlink data ("Y" in S162), the terminal 200 receives the
PDSCH signal (S163). For example, the separation unit 221 separates the
PDSCH signal and outputs the PDSCH signal to the PDSCH processing unit 225,
and the PDSCH processing unit 225 references control information relating to

the PDSCH output from the PDCCH processing unit 223 and decodes the
PDSCH signal.
[0099] The terminal 200, after receiving the PDSCH signal (S163), or upon
judging that control information for downlink data is not included ("N" in S162),
determines whether control information for uplink data is detected (S164). For
example, the PDCCH processing unit 223 can detect control information for
uplink data from the signal length of the PDCCH signal. Or, a Flag for format
0/format 1A differentiation included in the PDCCH signal can be used to
discriminate between control information relating to the PDSCH and control
information relating to the PUSCH. This control information for uplink data
includes the "CQI request", and is for example DCI format 0 control information.
[0100] When the control information for uplink data cannot be detected
("N" in S164), the terminal 200 does not receive the control information to
transmit user data and similar on the uplink, and so the series of processing
ends without performing this transmission.
[0101] On the other hand, upon determining that control information for
uplink data is detected ("Y" in S164), the terminal 200 detects whether one or
more "l"'s is included in the "CQI request" included in the control information
for uplink data (S165). For example, the PDCCH processing unit 223 can
perform detection by referencing the "CQI request" bits in the DCI format 0.
[0102] When one or more "1" is included in the "CQI request" ("Y" in S165),
the terminal 200 generates CSI for the DLCC specified by the "CQI request"
(S166). For example, the CSI generation unit 224 generates CSI for the DLCC
corresponding to the "CQI request" output from the PDCCH processing unit 223.
At this time, if there is user data to be transmitted, the terminal 200 also
generates the user data.
[0103] Next, the terminal 200 encodes the generated CSI and user data
(S167). For example, the CSI processing unit 227 references the control
information relating to the PUSCH and performs error correction encoding of
the CSI, and the user data processing unit 228 references the control
information relating to the PUSCH and performs error correction encoding of
user data.

[0104] Next, the terminal 200 multiplexes the CSI and user data and
generates the PUSCH signal (S168). For example, the PUSCH generation unit
229 multiplexes the CSI and user data, and generates the PUSCH signal to be
transmitted using the PUSCH.
[0105] Next, the terminal 200 transmits the generated PUSCH signal to the
base station 100 (S169). For example, the terminal 200 uses the UL CC
specified by the "carrier indicator" of the DCI format 0 to transmit the CSI after
the time of four subframes.
[0106] On the other hand, when one or more "1" is not included in the
detected "CQI request" ("N" in S165), the terminal 200 performs user data
generation (S170). In this case, the base station 100 is not specifying the
DLCC for aperiodic reporting, and thus the terminal 200 does not perform
aperiodic CSI reporting. The terminal 200 performs user data generation and
similar according to control information for uplink data.
[0107] That is, the terminal 200 encodes the generated user data and
generates a PUSCH signal (S171, S172). For example, the user data processing
unit 228 references the control information for uplink data (for example DCI
format 0 control information) output from the PDCCH processing unit 223, and
performs error correction encoding and similar of the user data.
[0108] Returning to FIG. 10, the base station 100 receives the PUSCH signal
transmitted from the terminal 200 (S17), and when CSI is included in the
PUSCH signal, extracts the CSI (S18). For example, the PUSCH processing unit
133 performs error correction decoding of the PUSCH signal and extracts the
CSI transmitted as a PUSCH signal, and the second separation unit 134
separates the user data and CSI to extract the CSI. By this means, the base
station 100 can receive the CSI for the specified DLCCs.
[0109] In this way, in the second embodiment the base station 100 can use
the control information for uplink data, such as for example the "CQI request"
of DCI format 0, to specify arbitrary DLCCs for which CSI reports are to be
made. Hence the base station 100 can cause the terminal 200 to report
information relating to the channel states for arbitrary bandwidths. Further, the

terminal 200 transmits the CSI for the specified DLCC, so that compared with a
case in which the CSI is transmitted for all DLCCs, throughput can be improved.
[0110] As another example in the second embodiment, for example DLCC
can be grouped, and the 5-bit "CQI request" can for example be reduced to 3
bits. FIG. 7B illustrates an example of grouping. For example, when 3 bits can
be transmitted as the "CQI request", one group is grouped as a maximum 3
CCs, and within one group a plurality of DLCCs for CSI report can be specified.
In this case, the base station 100 may transmit the "CQI request" specifying
DLCC for the CSI report through the DLCC included in the "PDCCH monitoring
set". Or, the base station 100 can perform transmission through at least one of
the DLCCs in the group. In this case also, the base station 100 uses at least
one of the plurality of DLCCs, and by transmitting at least one control
information item for uplink data including a 5-bit "CQI request", can cause CSI
report for the specified DLCC.
[0111] Third Embodiment
Next, a third embodiment is explained. Differences with the second
embodiment are mainly explained, and explanation of similar matter is omitted.
The third embodiment is an example in which the "CQI request" is added to the
control information for downlink data (for example, DCI formats 1,1A, IB, 1C,
ID, 2, 2A, 2B).
[0112] First, the DCI format is explained. A Format for the PDCCH signal
include DCI formats 1,1A and similar. These DCI formats are used selectively
according to the control signal application. Examples are cited below.
[0113] (0) DCI format 0 is used for example in PUSCH scheduling, as
explained in the second embodiment.
[0114] (1) DCI format 1 is for example used in normal PDSCH scheduling.
In DCI format 1, discontinuous radio resource can also be specified.
[0115] (1A) DCI format 1A is used in compact PDSCH scheduling. Compact
scheduling is a scheduling method in which, for example, continuous radio
resource is specified by a starting position and size. DCI format 1A is also used
for random access startup.

[0116] (1B) DCI format 1B is used for compact PDSCH scheduling when
providing notification including precoding information.
[0117] (1C) DCI format 1C is used in compact PDSCH scheduling such that
notification information is further decreased compared with DCI format 1A.
[0118] (1D) DCI format 1D is used in compact PDSCH scheduling when
notification includes both precoding information and power offset information.
[0119] (2) DCI format 2 is used in PDSCH scheduling when executing MIMO
under closed-loop control (closed-loop MIMO (Multiple Input Multiple Output)).
[0120] (2A) DCI format 2A is used in PDSCH scheduling when executing
MIMO under open-loop control (open-loop MIMO).
[0121] (2B) DCI format 2B is used in PDSCH scheduling when executing
dual layer transmission.
[0122] Thus each of the DCI formats 1 to 2B is the control information used
in PDSCH scheduling.
[0123] FIG. 12 illustrates an example of DCI format 1 parameters. As
illustrated in FIG. 12, in the third embodiment, 1 bit is further added to the
"CQI request" as a parameter of the control information for downlink data (for
example DCI format 1), indicating whether aperiodic CSI report is made.
[0124] FIG. 13 illustrates an example of PDCCH and PDSCH settings. In the
third embodiment, the base station 100 requests that the terminal 200 perform
aperiodic CSI report by setting the "CQI request" to "1" in the control
information for downlink data to which the "CQI request" is added. The base
station 100 transmits the control information for uplink data explained in the
second embodiment (for example, DCI format 0 in FIG. 6) to the terminal 200
as the PDSCH signal. When the "CQI request" of the control information for
downlink data is "1", the terminal 200 receives the PDSCH signal and extracts
for example the 5-bit "CQI request" (hereafter called the "detailed CQI
request") from the control information for uplink data. The terminal 200
generates the CSI for the DLCC specified by the detailed CQI request.
[0125] The control information for uplink data transmitted as the PDSCH
signal becomes, for example, control information when the terminal 200
transmits the CSI for the specified DLCC.

[0126] FIG. 14 illustrates an example of the configuration of the base
station 100 in the third embodiment. The scheduler 110 generates parameter
value of the detailed CQI request corresponding to the DL CC decided by the
report CC decision unit 111, and generates the control information for uplink
data (PUSCH) explained in the first embodiment (for example, the control
information of DCI format 0 (for example FIG. 6)). The scheduler 110 outputs
the generated DCI format 0 control information to the PDSCH generation unit
114. The PDSCH generation unit 114 outputs the DCI format 0 control
information to the multiplexing unit 115 as the PDSCH signal.
[0127] FIG. 15 illustrates an example of the configuration of the terminal
200 in the third embodiment. The terminal 200 further includes a separation
unit 235. The separation unit 235 includes for example the reception unit 21 in
the first embodiment.
[0128] The separation unit 235 separates the user data and control
information for uplink data (for example DCI format 0 control information)
output from the PDSCH processing unit 225, and separates the DCI format 0
control information into a detailed CQI request parameter value, and other
control information. The separation unit 235 outputs the detailed CQI request
to the CSI generation unit 224, and outputs the DCI format 0 control
information other than the detailed CQI request to the PUSCH generation unit
229.
[0129] Next, an example of operation in the third embodiment is explained.
FIG. 16 and FIG. 17 are flowcharts illustrating an operation example. Below,
the operation example of FIG. 16 and FIG. 17 is explained in the order of the
step numbers, but an explanation of portions similar to the second embodiment
is omitted.
[0130] The base station 100, upon deciding for which DLCC CSI report is to
be made (S11), generates the control information for downlink data (S20). For
example, the scheduler 110 generates the control information relating to the
PDSCH, such as for example DCI format 1 and 1A or other control information.
At this time, the scheduler 110 generates the control information in which the
added "CQI request" bit is set to "1".

[0131] Next, the base station 100 generates the control information for
uplink data (S21). For example, the scheduler 110 generates the control
information included in DCI format 0 (for example FIG. 6) to cause CSI
reporting.
[0132] Next, the base station 100 generates the parameter value of the
detailed CQI request (S22). For example, the scheduler 110 generates the
parameter value ("11100" or similar) corresponding to the CCs decided upon by
the report CC decision unit 111. By this means, the base station 100 can
specify the DLCC for which CSI report is to be made.
[0133] Next, the base station 100 generates user data (S23). For example,
the generated user data is input to the PDSCH generation unit 114.
[0134] Next, the base station 100 generates the PDCCH signal from the
control information for downlink data (S24). For example, the PDCCH
generation unit 113 generates the PDCCH signal for the DCI format 1 or other
control information output from the scheduler 110.
[0135] Next, the base station 100 generates the PDSCH signal from the
control information for uplink data, detailed CQI request, and user data (S25).
For example, the PDSCH generation unit 114 generates the PDSCH signal for
DCI format 0 the control information output from the scheduler 110 and user
data output from a higher-order apparatus.
[0136] Next, the base station 100 transmits the PDCCH signal and the
PDSCH signal to the terminal 200 (S26).
[0137] The terminal 200 performs terminal-side processing of these signals
(S27). FIG. 17 is a flowchart illustrating an example of terminal-side processing.
[0138] When the control information for downlink data is not included in the
received PDCCH signal ("N" in S162), no DCI format 1, 1A or other control
information (for example FIG. 12) is received, and the terminal 200 does not
perform CSI reporting (S270).
[0139] On the other hand, when the control information for downlink data is
received ("Y" in S162), the terminal 200 references the "CQI request" bit of the
control information and determines whether the bit is "1" (S271). For example,
the DCI format 1, 1A or other control information extracted by the PDCCH

processing unit 223 is referenced, and a determination is made as to whether
the "CQI request" bit is "1".
[0140] If the bit is not "1" ("N" in S271), the terminal 200 does not perform
CSI reporting, but references the control information for downlink data and
receives the PDSCH signal (S272). If the "CQI request" bit is not "1", the base
station 100 does not specified that CSI reporting be performed non-periodically,
and thus the terminal 200 does not perform aperiodic CSI reporting. However,
the terminal 200 receives the control information for downlink data, and so
receives the PDSCH signal accordingly. For example, the PDSCH processing
unit 225 references the control information for downlink data output from the
PDCCH processing unit 223 and decodes the PDSCH signal.
[0141] On the other hand, if the "CQI request" of the control information for
downlink data is "1" ("Y" in S271), the terminal 200 references the control
information for downlink data and receives the PDSCH signal (S273), and
extracts the DCI format 0 control information included in the PDSCH signal
(S274). For example, the PDSCH processing unit 225 extracts the DCI format 0
control information from the PDSCH signal and outputs the DCI format 0
control information to the separation unit 235. Of the DCI format 0 control
information, the separation unit 235 outputs the detailed CQI request
parameter value to the CSI generation unit 224, and outputs the other
parameter value to the PUSCH generation unit 229.
[0142] Thereafter, the CSI generation unit 224 generates CSI for DLCC
specified by the detailed CQI request (S166), and the terminal 200 transmits
the CSI for the specified DLCC to the base station 100 (S167 to S169, S17, S18).
[0143] Thus, in the third embodiment also, the information (the detailed
CQI request) specifying for which DLCC the CSI is to be reported is transmitted
to the terminal 200 by the PDSCH signal. Hence, in the third embodiment also,
the base station 100 causes the terminal 200 to report information relating to
the channel state for arbitrary frequency band. Further, compared with a case
in which the terminal 200 transmits CSI for all CCs, the terminal 200 transmits
CSI for the specified DL CC, so that throughput can be improved.

[0144] In the operation example of the third embodiment (FIG. 16), the
order of generation of control information for downlink data and control
information for uplink data (S20, S21) may be reversed. Further, the order of
generation of the PDCCH and generation of the PDSCH (S24, S25) may also be
reversed.
[0145] Fourth Embodiment
Next, a fourth embodiment is explained. Differences with the second and
third embodiments are mainly explained, and explanation of similar matter is
omitted. The fourth embodiment is an example in which, when requesting
aperiodic CSI report, interpretation of the control information for uplink data
(for example DCI format 0) is changed.
[0146] FIG. 18A and FIG. 18B illustrate example of the DCI format 0
parameter. When the "CQI request" bit is "1" (when aperiodic CSI reports are
requested), the DCI format 0 parameter is taken to be parameter indicating the
control information for downlink data, as in FIG. 18B, rather than parameter
indicating the control information for uplink data. When "CQI request" is "0"
(aperiodic CSI report is not requested), the parameter indicate the usual control
information for uplink data, as in FIG. 18A.
[0147] FIG. 19A and FIG. 19B illustrate PDCCH and PDSCH setting examples
respectively. When the base station 100 does not cause the terminal 200 to
perform aperiodic CSI report, the base station 100 transmits the DCI format 0
control information in which "CQI request" is set to "0" as the PDCCH signal.
[0148] On the other hand, when the base station 100 causes the terminal
200 to perform aperiodic CSI reporting, the base station 100 transmits, as the
PDCCH signal, the DCI format 0 control information including control
information for downlink data in which "CQI request" is set to "1". And, the
base station 100 transmits to the terminal 200, as the PDSCH signal, the control
information for uplink data (for example the DCI format 0 in FIG. 6) in which
the DLCC for CSI reporting is specified as a detailed CQI request.
[0149] Examples of the configurations of the radio communication system,
base station 100, and terminal 200 in the fourth embodiment can be

implemented similarly to those of the third embodiment (for example FIG. 14
and FIG. 15).
[0150] FIG. 20 and FIG. 21 are flowcharts illustrating an operation example.
The operation example is explained in the order of the step numbers, focusing
mainly on differences with the third embodiment.
[0151] The base station 100 decides for which DL CC the CSI report is to be
made (S11), and generates the PDCCH signal and the PDSCH signal (S30). In
this case, for example, the DCI format 0 parameter value for which the
interpretation is changed (for example FIG. 18B) are included in the PDCCH
signal. The PDSCH signal includes, as the control information for uplink data,
the DCI format 0 parameter value explained in the second embodiment. The
DCI format 0 parameter value included in the signal transmitted as this PDSCH
signal include, for example, 5 bits of the detailed CQI request. For example,
the scheduler 110 generates each of the parameter value, the PDCCH
generation unit 113 generates the PDCCH signal, and the PDSCH generation
unit 114 generates the PDSCH signal.
[0152] Next, the base station 100 transmits the generated PDCCH signal
and PDSCH signal to the terminal 200 (S31). For example, the multiplexing unit
115 and radio transmission unit 116 transmit the signals as the radio signal to
the terminal 200.
[0153] Next, the terminal 200 performs terminal-side processing (S32). FIG.
21 is a flowchart illustrating an example of terminal-side processing. After
receiving the PDCCH signal (S161), the terminal 200 discriminates whether the
control information for uplink data is detected (S320). For example, the PDCCH
processing unit 223 discriminates whether the PDCCH signal for control
information for uplink data is received through the signal length of the PDCCH
signal and a Flag for format 0/format 1A differentiation included in the PDCCH
signal. If control information for uplink data cannot be detected ("N" in S320),
the terminal 200 does not perform aperiodic CSI reporting.
[0154] On the other hand, when the control information for uplink data is
detected in the PDCCH signal ("Y" in S320), the terminal 200 confirms the "CQI
request" from the control information for uplink data transmitted by the PDCCH

signal (S271), and thereafter performs processing similar to that of the third
embodiment.
[0155] Thus, in the fourth embodiment also, the base station 100 can use
the detailed CQI request to specify the DLCC for which aperiodic CSI reporting
is to be performed. Hence, similarly to the third embodiment, the base station
100 can cause the terminal 200 to report the information relating to channel
state for arbitrary frequency bands. Further, because the terminal 200
transmits CSI for specified DLCC, compared with a case in which the CSI is
transmitted for all CCs, throughput can be improved.
[0156] Fifth Embodiment
Next, a fifth embodiment is explained. Differences with the second
embodiment are mainly explained, and explanation of similar matter is omitted.
The fifth embodiment is an example in which the terminal 200 performs CSI
reporting through the correspondence relationship between DLCC set in the
"PDCCH monitoring set" (hereafter called "PDCCH monitoring CCs"), and DLCC
with PDSCH scheduling (hereafter called "scheduled DLCC").
[0157] FIG. 22A illustrates an example of the correspondence relation
between PDCCH monitoring CCs and scheduled DLCC; FIG. 22B illustrates an
example of DLCC for which CSI reporting is performed. As explained in the first
embodiment, the PDCCH monitoring CC is a DLCC for which, for example, there
is the possibility that the PDCCH is set for the terminal 200. In the example of
FIG. 22A, the PDCCH monitoring CCs are DLCC#1 and DLCC#4. In the PDCCH
of DLCC#1, the setting is made so as to perform scheduling for the PDSCH of
DLCC#1 to #3. In this case, DLCC#1 to #3 are set as scheduled DLCCs for the
DLCC#1, which is the PDCCH monitoring CC. Similarly, DLCC#4 and #5 are set
as scheduled DLCCs for the DLCC#4, which is set as the PDCCH monitoring CC.
[0158] In such a correspondence relationship, as illustrated in FIG. 22B,
when the base station 100 transmits the control information for uplink data
using the DLCC#1 with "CQI request" set to "1" (for example, causing aperiodic
reporting), the terminal 200 transmits the CSI for DLCC#1 to #3 to the base
station 100. Further, when the base station 100 transmits the control
information for uplink data using the DLCC#4 with "CQI request" set to "1", the

terminal 200 transmits the CSI for DLCC#4 and DLCC#5 to the base station 100.
The terminal 200 reports the CSI for DLCC#1 to #3, for which it is possible that
scheduling is performed using the control information transmitted using
DLCC#1.
[0159] Next, examples of the configurations of the base station 100 and
terminal 200 in the fifth embodiment are explained. FIG. 23 and FIG. 24
illustrate examples of the configurations of the base station 100 and terminal
200 respectively.
[0160] The base station 100 further includes an upper layer 140. The upper
layer 140 generates a correspondence relation table (for example FIG. 22A)
between the PDCCH monitoring CC and the scheduled DLCC, and outputs the
table as a control data to the PDSCH generation unit 114. Also, upper layer
140 outputs the correspondence relation table to the scheduler 110.
[0161] The PDSCH generation unit 114 performs error correction encoding
and similar of the control data from the upper layer 140, and outputs the result
as the PDSCH signal to the multiplexing unit 115. The scheduler 110 or report
CC decision unit 111 decides the DLCC for CSI reporting based on the
correspondence relation table, and performs scheduling.
[0162] The terminal 200 further includes an upper layer 240. The upper
layer 240 inputs the control data extracted by error correction decoding and
similar in the PDSCH processing unit 225, and generates or holds the
correspondence relation table. The upper layer 240 outputs the
correspondence relation table to the CSI generation unit 224.
[0163] The CSI generation unit 224 holds a same correspondence relation
table as the correspondence relation table generated by the base station 100.
The CSI generation unit 224 generates the CSI for scheduled DLCC for the
PDCCH monitoring CC for which the "CQI request" bit is "1", based on this table.
[0164] Next, an example of operation in the fifth embodiment is explained.
FIG. 25 and FIG. 26 are flowcharts illustrating the operation example. This
operation example is also explained focusing on difference with the second
embodiment and similar.

[0165] First, the base station 100 sets associations between the PDCCH
monitoring CC and scheduled DLCC (S40). For example, the upper layer 140 of
the base station 100 uses carrier aggregation setting to set which bandwidth is
which CC, which CC is the PDCCH monitoring CC, and which CC is scheduled
DLCC, and similar. At this time, the upper layer 140 generates the
correspondence relation table between the PDCCH monitoring CC and
scheduled DLCC.
[0166] Next, the base station 100 provides notification of these settings
(S41). For example, together with relations between band and CC set using
carrier aggregation setting by the upper layer 140, the correspondence relation
table is output to the PDSCH generation unit 114 as the control data (or a
setting information). The control data is transmitted to the terminal 200 as the
PDSCH signal by the PDSCH generation unit 114.
[0167] The terminal 200 receives the control data transmitted using the
PDSCH (S42). For example, the PDSCH processing unit 225 extracts the control
data from the PDSCH signal, and outputs the result to the upper layer 240.
[0168] Next, the terminal 200 saves the received control data (S43). For
example, the upper layer 240 saves the control data.
[0169] From the above, the base station 100 and terminal 200 share
correspondence relations between the PDCCH monitoring CC and scheduled
DLCC (for example FIG. 22A). When the report CC decision unit 111 decides
for which CC CSI report is to be made, the scheduler 110 uses the PDCCH
monitoring CC corresponding to the decided DLCC to transmit the control
information for uplink data based on the correspondence relation table (S10 to
S15). For example, in the example of FIG. 22A, when CSI reporting is to be
performed for DLCC#3, the base station 100 transmits the control information
for uplink data (for example DCI format 0) with the "CQI request" bit set to "1"
in the DLCC#1.
[0170] The terminal 200 receives this information and performs terminal-
side processing (S45). For example, upon receiving the PDCCH signal in
DLCC#1, based on the control information for downlink data transmitted using

the PDCCH signal, the terminal 200 receives the PDSCH signals for DLCC#1 to
CC#3, which are scheduled DLCCs (S161, "Y" in S162, S163).
[0171] Next, the terminal 200 detects whether the control information for
uplink data is received (S450). For example, the PDCCH processing unit 223
performs detection based on the signal length of the received PDCCH signal
and the Flag for format 0/format 1A differentiation included in the PDCCH
signal. When the control information for uplink data is not received ("N" in
S450), the terminal 200 ends the series of processing without performing
aperiodic CSI reporting.
[0172] On the other hand, when the control information for uplink data is
received ("Y" in S450), the terminal 200 determines whether the "CQI request"
bit in the control information is "1" (whether aperiodic CSI reporting is
performed) (S271).
[0173] When the bit is "1" ("Y" in S271), the terminal 200 performs CSI
reporting for the corresponding scheduled DLCC based on the correspondence
relation table (S451). For example, based on the frequency band of the
received PDCCH signal, the PDCCH processing unit 223 outputs the information
of which DLCC is used to transmit DCI format 0 together with the "CQI request"
bit to the CSI generation unit 224. The CSI generation unit 224 takes the DLCC
in which DCI format 0 is transmitted to be the PDCCH monitoring CC, and
selects the scheduled DLCC based on the correspondence relation table, and
generates the CSI with the DLCC as the CC for the CSI report (S451).
[0174] On the other hand, when the "CQI request" bit is not "1" ("N" in
S271), the terminal 200 need not perform aperiodic CSI reporting, and
references the control information for uplink data to perform user data
generation and similar (S170 to S172).
[0175] Then, the terminal 200 transmits the generated CSI to the base
station 100 (S169). At the time of transmission, in the case of cross-carrier
scheduling for example, the terminal 200 performs transmission using the UL
CC specified by the "carrier indicator" of DCI format 0 (for example FIG. 6).
[0176] Or, the terminal 200 may perform CSI transmission using the
scheduled ULCC. In addition to DLCCs, there are also ULCCs for which the

PDCCH can be set as PDCCH control information by the PDCCH monitoring CC.
The terminal 200 can be made to use such the ULCC to transmit CSI.
[0177] FIG. 27 illustrates an example of the correspondence relation
between the PDCCH monitoring CC and scheduled ULCC. For example, similarly
to a correspondence relation between the PDCCH monitoring CC and scheduled
DLCC, the base station 100 sets and transmits as setting information (or control
data) (S40, S41), and the terminal 200 shares the correspondence relation by
receiving and saving the setting information (S42, S43). For example, when
the base station 100 transmits the control information for uplink data with "CQI
request" set to "1" in DLCC#1, the terminal 200 uses the carrier indicator to
specify one of ULCC#1 to ULCC#3, and uses the specified ULCC to transmit the
generated CSI.
[0178] Thus, in the fifth embodiment also, the base station 100 uses the
correspondence relation between the PDCCH monitoring CC and scheduled
DLCC to decide DLCC for which CSI reporting is performed. The base station
100 can cause CSI reporting for DLCC set as scheduled DLCC, and can cause
the terminal 200 to report the information relating to the channel state of
arbitrary frequency bands. Further, the terminal 200 is caused to report the
CSI for DLCC set as scheduled CC, so that compared with a case in which the
CSI is reported for all DLCCs, throughput can be improved. Further, in the fifth
embodiment, there is no increase in the number of bits in DCI format 0 or
similar, so that preexisting data structures can be used as-is, and there is no
increase in overhead due to control signaling.
[0179] Sixth Embodiment
Next, a sixth embodiment is explained. Differences with the fifth
embodiment are mainly explained, and explanation of similar matter is omitted.
The sixth embodiment is an example in which, separately from scheduled DLCC,
DLCC for CSI reporting is determined in advance for PDCCH monitoring CC.
[0180] FIG. 28A illustrates an example of the relation between the PDCCH
monitoring CC and scheduled DLCC and DLCC for CSI reporting. FIG. 28B
illustrates an example of DLCC for CSI reporting.

[0181] For example, as illustrated in FIG. 28A, even when there is a
correspondence relation between the PDCCH monitoring CC and scheduled
DLCC, DLCC to cause CSI reporting for monitoring DLCC#1 can be set to
DLCC#1 and DLCC#2, and DLCC to cause CSI reporting for monitoring DLCC
#4 can be set to DLCC#3, DLCC#4 and DLCC#5. For example, when the base
station 100 is to cause the terminal 200 to perform CSI reporting for DLCC#3,
the DLCC#4, which is the PDCCH monitoring CC, is used to transmit the control
information for uplink data (for example DCI format 0) with the "CQI request"
bit set to "1". Based on the correspondence relation, the terminal 200 performs
CSI reporting for DLCC#3 to #5. By this means, the base station 100 can
receive CSI reports for DLCC#3.
[0182] Examples of configuration of the base station 100 and terminal 200
can be implemented similarly to the fifth embodiment (for example FIG. 23 and
FIG. 24). FIG. 29 and FIG. 30 are flowcharts of an operation example.
[0183] When making carrier aggregation setting, the upper layer 140 of the
base station 100 generates a correspondence relation between the PDCCH
monitoring CC and the DL CC for CSI reporting, holds this as the
correspondence relation table (for example FIG. 28A), and transmits this to the
terminal 200 (S50, S41).
[0184] On the other hand, the upper layer 240 of the terminal 200, by
holding the correspondence relation table received as the control data (S42,
S43), can share information on CCs for CSI reporting with the base station 100.
[0185] The base station 100 decides the DL CC for which CSI reporting is to
be performed. Based on the correspondence relation table (for example FIG.
28A), the DLCC in which the PDCCH signal is to be transmitted is decided (S51).
For example, the scheduler 110 references the correspondence relation table
from the higher-level layer 104, and based on the table decides on the DLCC for
transmission.
[0186] Then, the base station 100 uses the DLCC thus decided to transmit
control information for uplink data with the "CQI request" bit set to "1" (S14,
S15).

[0187] On the other hand, the terminal 200 performs terminal-side
processing (S52), detects whether DCI format 0 control information is included
in the received PDCCH signal (S450), and if detected ("Y" in S450), references
the "CQI request" bit included in the DCI format control information (S271).
[0188] When the "CQI request" bit included in the control information for
uplink data is "1" ("Y" in S271), the DLCC for CSI reporting corresponding to
the DLCC in which the PDCCH signal is transmitted is read out based on the
correspondence relation table. Then, the terminal 200 performs CSI reporting
for the DLCC (S520). For example, the CSI generation unit 224 takes as input
information on the DLCC in which the PDCCH signal was transmitted from the
PDCCH processing unit 223, references the correspondence relation table from
the upper layer 240, and decides the DLCC for CSI reporting corresponding to
the DLCC. The CSI generation unit 224 then generates CSI for the DLCC thus
decided.
[0189] The terminal 200 then transmits the generated CSI to the base
station 100 (S169). For example, similarly to the fifth embodiment, the
terminal 200 may use the UL CC specified by the "carrier indicator" of DCI
format 0 for transmission, or may use the scheduled ULCC (for example FIG.
27) for transmission.
[0190] In this way, in the sixth embodiment also, the base station 100 can
specify arbitrary DLCC for reporting based on a correspondence relation with
PDCCH monitoring CCs. Hence the base station 100 can cause the terminal 200
to report information relating to channel states for arbitrary frequency band.
Further, the terminal 200 can perform CSI reporting for CC set as DLCC for CSI
reporting. Hence compared with a case in which the terminal 200 performs CSI
reporting for all ULCCs, quantity of the information transmitted is reduced, so
that throughput can be improved.
[0191] Seventh Embodiment
Next, a seventh embodiment is explained. Differences with the fifth
embodiment are mainly explained, and explanation of similar matter is omitted.
The seventh embodiment is an example in which the correspondence relation
between the ULCC in which the PUSCH signal is transmitted and the DLCC for

CSI reporting is set, and the terminal 200 performs CSI reporting based on this
correspondence relation.
[0192] FIG. 31A and FIG. 31B illustrate examples of correspondence relation
between the ULCC used to transmit PUSCH signal, and DLCC for CSI reporting;
FIG. 31C illustrates an example of DLCC for which CSI reporting is performed.
[0193] As explained in the second embodiment, when cross-carrier
scheduling is performed, the DCI format 0 control information includes a
"carrier indicator" which indicates for example which ULCC is used to transmit
the PUSCH signal. The DLCC for which CSI report is to be made is associated
with the ULCC to be used to transmit the PUSCH signal, and CSI reporting is
performed based on this correspondence relation.
[0194] For example, when the base station 100 is to cause CSI reporting for
DLCC#3, the following processing is performed. From the correspondence
relation (for example FIG. 31A), the ULCC corresponding to CC#3 as the DLCC
for CSI reporting is one of ULCC#1 to CC#3. The base station 100 decides on
the ULCC to be used to transmit the PUSCH signal (for example ULCC#1) from
ofULCC#ltoCC#3.
[0195] The base station 100 may decide on all of the ULCC#1 to CC#3 as
ULCC to transmit the PUSCH signal. The base station 100 generates the control
information for uplink data specifying ULCC#1 as the ULCC for transmitting the
PUSCH signal (for example, in the case of DCI format 0, "carrier indicator" =
ULCC#1). The PDCCH signal for the control information may be transmitted
using any DLCC in the case of cross-carrier scheduling (for example, using a
PDCCH monitoring CC); in the example of FIG. 31C, DLCC#1 is used for
transmission. In the case of same-carrier scheduling, the base station 100
transmits the PDCCH signal using DLCC#1. Because ULCC#1 is specified as the
ULCC for transmission of the PUSCH signal, the terminal 200 performs CSI
reporting for DLCC#1 to CC#3 based on the correspondence relation. By this
means, the base station 100 can receive CSI reports for DLCC#3.
[0196] As illustrated in FIG. 31B, the correspondence between the ULCC
and DLCC for CSI reporting may be such that different DLCC is specified for CSI
reporting for each ULCC. Further, not all ULCCs need have information on

DLCCs for reporting, and a portion of the ULCCs may have DLCCs for CSI
reporting.
[0197] Examples of the configuration of the base station 100 and terminal
200 can be implemented similarly to the fifth embodiment (for example FIG. 23
and FIG. 24). FIG. 32 and FIG. 33 are flowcharts of an operation example.
The operation example is explained in the order of the step numbers, focusing
mainly on differences with the fifth embodiment.
[0198] First, in carrier aggregation settings, the base station 100 sets an
association between the ULCC transmitting the PUSCH signal and DLCC for CSI
reporting (S60). For example, the upper layer 140 performs settings and
generates the table indicating the correspondence relation (for example FIG.
31A). The base station 100 notifies the terminal 200 of the correspondence
relation as the control data (S41), and the terminal 200 receives this, and saves
the data as the table (S42, S43). For example, the upper layer 240 saves the
data as the table. By this means, the correspondence relation is shared
between the base station 100 and terminal 200.
[0199] The base station 100 decides for which DLCC CSI reporting is to be
performed (Sll), and decides the ULCC to use in transmitting the PUSCH signal
according to these DLCC (S61). For example, the scheduler 110 references the
correspondence table (for example FIG. 31A) according to the DLCC decided by
the report CC decision unit 111, and decides the ULCC to transmit the PUSCH
signal. Then, the base station 100 generates the PDCCH signal specifying this
ULCC, and transmits the PDCCH signal to the terminal 200 (S14, S15).
[0200] The terminal 200 performs terminal-side processing (S62), and upon
receiving the control information for uplink data ("Y" in S450 in FIG. 33),
detects whether the "CQI request" bit is set to "1" (perform aperiodic CSI
reporting) (S271).
[0201] Then, when the "CQI request" bit is "1" ("V in S271), the terminal
200 references the correspondence table (for example FIG. 31A) and decides
the DLCC for CSI reporting corresponding to the ULCC transmitting the PUSCH
signal, and generates the CSI for the DLCC thus decided (S620). For example,
the PDCCH processing unit 223 extracts from the PDCCH signal the information

as to which ULCC transmitted the PUSCH signal. In the case of cross-carrier
scheduling, by extracting the "carrier indicator" included in the DCI format 0
control information, the information as to which ULCC is used to transmit the
PUSCH signal can be extracted. In the case of same-carrier scheduling, the
PDCCH processing unit 223 can perform extraction from the relation with the
reception frequency band of the received PDCCH signal. The PDCCH
processing unit 223 outputs to the CSI generation unit 224 an information
indicating which ULCC transmits the PUSCH signal. The CSI generation unit
224 references the correspondence relation table from the upper layer 240 for
the ULCC transmitting the PUSCH signal, decides the DLCC for CSI reporting,
and generates the CSI for these DLCC.
[0202] The terminal 200 transmits the generated CSI using the specified
ULCC (S169). By receiving this (S17, S18), the base station 100 can receive the
CSI for the DLCC for CSI reporting.
[0203] In the seventh embodiment also, the base station 100 can receive
the CSI for DLCC for reporting by specifying the ULCC to transmit the PUSCH
signal, and so can cause the terminal 200 to report information relating to
channel states for arbitrary frequency band. Further, the terminal 200 reports
the CSI for CCs specified as the DLCC for CSI reporting. Hence compared with
a case in which the terminal 200 performs CSI reporting for all DLCCs, quantity
of the information transmitted is reduced, so that throughput can be improved.
[0204] Eighth Embodiment
Next, an eighth embodiment is explained. Differences with the second
embodiment are mainly explained, and explanation of similar matter is omitted.
The eighth embodiment is an example in which a field for specifying DLCC for
CSI reporting is added to the control information for uplink data (for example
DCI format 0).
[0205] FIG. 34 illustrates an example of the DCI format 0 parameters in the
eighth embodiment. In the DCI format, there is a "CQI report carrier indicator"
field. The "CQI report carrier indicator" is a field used for example to specify
DLCC for which CSI reporting is to be performed, of the plurality of DLCCs.
When the base station 100 inserts the parameter value (3 bits) into this field

and transmits to the terminal 200 as the PDCCH signal, the terminal 200
performs CSI reporting for the specified DLCC.
[0206] FIG. 35 illustrates an example of DLCC for which CSI reporting is
performed. When the base station 100 sets the "CQI request" bit to "1" and
specifies "000" in the "CQI report carrier indicator" field, the terminal 200
performs CSI reporting for the DLCC#1 corresponding to "000". For example,
when the "CQI report carrier indicator" bits are "001", the terminal 200
performs CSI reporting for DLCC#2. The correspondence relation between the
bit value (parameter value) of the "CQI report carrier indicator" field and the
DLCC for reporting may for example be set at a time when the carrier
aggregation is set, similarly to the fifth embodiment, and is notified to the
terminal 200.
[0207] The base station 100 and terminal 200 in the eighth embodiment can
be implemented similarly to the second embodiment (for example FIG. 8 and
FIG. 9), or similarly to the fifth embodiment (for example FIG. 23 and FIG. 24).
FIG. 36 and FIG. 37 are flowcharts illustrating an operation example in the
eighth embodiment. The operation example is explained in the order of the
step numbers, focusing mainly on differences with the second embodiment.
[0208] The base station 100 decides, by means of the report CC decision
unit 111, for which DLCC CSI reporting is to be performed (Sll), and generates
the "CQI report carrier indicator" according to the DLCC thus decided (S70).
For example, the scheduler 110 decides parameter value of the "CQI report
carrier indicator" so as to correspond to the DLCC for reporting. At this time,
the scheduler 110 generates the control information for uplink data in which the
"CQI request" is set to "1" (to cause aperiodic CSI reporting). For example, the
scheduler 110 creates the parameter value for each field of the DCI format 0,
and based on these parameter value the PDCCH generation unit 113 generates
the PDCCH signal for the control information for uplink data.
[0209] Then, the base station 100 transmits the PDCCH signal to the
terminal 200 (S14, S15).
[0210] Next, the terminal 200 performs terminal-side processing (S71).
That is, the terminal 200 receives the PDCCH signal (S161 in FIG. 37), and

upon receiving the PDCCH signal for control information for uplink data ("Y" in
S450), detects whether the "CQI request" bit is "1" (S271).
[0211] When the "CQI request" bit is "1" ("Y" in S271), the terminal 200
references the "CQI report carrier indicator" field, and generates CSI for the
DLCC corresponding to the parameter value included in the field (S710). For
example, the PDCCH processing unit 223 extracts each of the parameter values
of DCI format 0 from the PDCCH signal, and outputs to the CSI generation unit
224 the parameter values included in "CQI report carrier indicator" as well as
"CQI request". TTie CSI generation unit 224 generates CSI for the
corresponding DLCC according to the parameter values of "CQI request" and
"CQI report carrier indicator".
[0212] Then, the terminal 200 transmits the generated CSI to the base
station 100 (S169), and by receiving this, the base station 100 can receive the
CSI for any one DLCC specified by the "CQI report carrier indicator".
[0213] Thus in the eighth embodiment also, the base station 100 can cause
CSI reporting to be performed for any DLCC, so that the terminal 200 can be
made to report the information relating to the channel state for the arbitrary
frequency band. Further, the terminal 200 reports the CSI for the CC specified
by the "CQI report carrier indicator". Hence compared with a case in which the
terminal 200 performs CSI reporting for all DLCCs, quantity of the information
transmitted is reduced, so that throughput can be improved.
[0214] In the eighth embodiment, for example 3 bits can be specified using
the "CQI report carrier indicator". When there are 4 or more DLCCs, the "CQI
report carrier indicator" can be used to specify any one of the DLCCs. When
there are 3 or fewer DLCCs, all combinations of arbitrary DLCCs can be
specified.
[0215] Ninth Embodiment
Next, a ninth embodiment is explained. Differences with the fifth
embodiment are mainly explained, and explanation of similar matter is omitted.
The ninth embodiment is an example in which the "carrier indicator" of control
information for uplink data (for example DCI format 0) is used to specify the
DLCC for CSI reporting.

[0216] As explained in the fifth embodiment, in cross-carrier scheduling, the
ULCC to transmit the PUSCH signal can be specified by the "carrier indicator".
When aperiodic CSI reporting is to be performed (when for example the "CQI
request" bit is "1"), the base station 100 specifies the "carrier indicator"
specifying the ULCC as the DLCC for CSI reporting. However, in this case the
ULCC for transmitting the CSI cannot be specified, and so the terminal 200
transmits the CSI using the ULCC determined in advance.
[0217] On the other hand, when aperiodic CSI reporting is not to be
performed (when for example the "CQI request" bit is "0"), the base station 100
uses the "carrier indicator" as usual to specify the ULCC for transmission of the
PUSCH signal.
[0218] FIG. 38A illustrates an example of the DLCC for reporting, and FIG.
38B illustrates an example of the ULCC to perform CSI reporting. As illustrated
in FIG. 38A, when for example CSI reporting is to be performed for the DLCC#1,
the base station 100 transmits a DCI format 0 PDCCH signal in which the "CQI
request" bit is "1" and the "carrier indicator" is "000". Because the DCI format
0 "CQI request" bit is "1", the terminal 200 interprets the "carrier indicator" to
be the DLCC for CSI reporting, and generates CSI for the DL CC#1
corresponding to "000". The terminal 200 for example uses the ULCC#3
determined in advance to transmit the CSI to the base station 100. By this
means, the base station 100 can cause the terminal 200 to perform CSI report
for the specified DLCC. Because the parameter value of the "carrier indicator"
field is for example 3 bits, as explained in the eighth embodiment, the number
of DLCCs for reporting is decided by the number of DLCCs set in carrier
aggregation. That is, when there are 4 or more DLCCs, one of the DLCCs can
be specified, and when there are 3 or fewer DLCCs, all combinations of
arbitrary DLCCs can be specified.
[0219] The base station 100 and terminal 200 in the ninth embodiment can
be implemented similarly to the second embodiment (for example FIG. 8 and
FIG. 9) or similarly to the fifth embodiment (FIG. 23 and FIG. 24). FIG. 39 and
FIG. 40 are flowcharts illustrating an operation example in the ninth
embodiment. The operation example is explained in the order of the step

numbers, focusing mainly on differences with the second and fifth
embodiments.
[0220] The base station 100 performs carrier aggregation setting, and
performs setting which ULCC is used to perform CSI report (S80). For example,
the upper layer 140 sets the ULCC#3 as the ULCC for CSI reporting.
[0221] The base station 100 then transmits this setting information to the
terminal 200 as the control data (S41). The terminal 200 receives the control
data, and saves the data as setting information (S42, S43). For example, the
upper layer 240 takes as input the ULCC for CSI reporting and saves this as the
setting information. By this means, the information as to which ULCC is used
for CSI transmission is shared between the base station 100 and the terminal
200.
[0222] The base station 100 decides the DLCC for which reporting is to be
performed (Sll), and generates the "carrier indicator" according to the DLCC
thus decided (S81). For example, the scheduler 110 generates a parameter
value for the "carrier indicator" according to the DLCC decided by the report CC
decision unit 111. When reporting of DLCC#1 is to be performed, the
parameter value of the "carrier indicator" is "000"; when reporting is to be
performed for DLCC#3, the parameter value is "010", and similar. The
scheduler 110 also sets the "CQI request" to "1". Then, the base station 100
generates the PDCCH signal of control information for uplink data including
these parameter values, and transmits the PDCCH signal to the terminal 200
(S14, S15).
[0223] The terminal 200 performs terminal-side processing (S82), and
receives the PDCCH signal (S161 in FIG. 40). When the "CQI request" is "1",
the terminal 200 references the "carrier indicator" parameter, and generates the
CSI for the DLCC corresponding thereto (S820). For example, the PDCCH
processing unit 223 extracts the "CQI request" and "carrier indicator" parameter
values from the PDCCH signal, and outputs the value to the CSI generation unit
224. The CSI generation unit 224 references the setting information saved in
the upper layer 240, and generates the CSI for the DLCC corresponding to the
parameter value of the "carrier indicator".

[0224] Then, the terminal 200 uses the ULCC set in advance to transmit the
generated CSI (S169). For example, the upper layer 240 notifies the PUSCH
generation unit 229 of the ULCC for transmission, and the PUSCH generation
unit 229 saves this information. The PUSCH generation unit 229 generates the
PUSCH signal including a CSI report, and outputs the PUSCH signal so as to be
transmitted to the terminal 200 using the saved ULCC.
[0225] The base station 100 receives the CSI for the DLCC specified by the
ULCC determined in advance (S17, S18).
[0226] In the ninth embodiment also, the base station 100 can use the
"carrier indicator" to cause CSI reporting for a specified DLCC, and so can cause
the terminal 200 to report the information relating to channel state in the
arbitrary frequency band. Further, the terminal 200 reports the CSI for the
DLCC specified by the "carrier indicator". Hence compared with a case in which
the terminal 200 performs CSI reporting for all DLCCs, quantity of the
information transmitted is reduced, so that throughput can be improved.
[0227] Tenth Embodiment
Next, a tenth embodiment is explained. Differences with the fifth
embodiment are mainly explained, and explanation of similar matter is omitted.
The tenth embodiment is an example in which the base station 100 causes CSI
reporting by associating a subframe number and the DLCC for CSI reporting.
[0228] FIG. 41 illustrates an example of the DLCC for CSI reporting. In the
case of cross-carrier scheduling, as described above, the PDCCH signal for the
control information for uplink data (for example DCI format 0) includes the
"carrier indicator" to indicate the ULCC for transmission of the PUSCH signal. In
the case of same-carrier scheduling, the ULCC with the same number as the
DLCC which transmitted the PDCCH signal for DCI format 0 is indicated. In the
tenth embodiment, the correspondence relation is set in advance between the
ULCC for transmission of the PUSCH signal and the subframe number in which
the DCI format 0 PDCCH signal is transmitted and the DLCC for CSI reporting,
and the base station 100 causes the terminal 200 to perform CSI reporting for
the DLCC specified based on this relation. On the other hand, the terminal 200

performs CSI reporting for the corresponding DLCC based on this
correspondence relation.
[0229] In the example of FIG. 41, for example the base station 100 uses the
subframe "0" to transmit a DCI format 0 PDCCH signal with a specification that
ULCC#1 be used to transmit the PUSCH signal. The terminal 200 generates the
CSI for DLCC#1, for example, based on the correspondence relation, from the
ULCC#1 transmitting the PUSCH signal and the subframe number "0". Hence
in order to cause CSI reporting for DLCC#1, the base station 100 may specify
that the ULCC#1 transmit the PUSCH signal, and that the PDCCH signal be
transmitted using subframe number "0". In the Da format 0 PDCCH signal,
the ULCC#1 can be specified during cross-carrier scheduling by specification
using the "carrier indicator", and during same-carrier scheduling can be
specified by having the PDCCH signal transmitted using DLCC#1. The base
station 100 sets the "CQI request" to "1" in the DCI format 0 control
information in order to cause aperiodic CSI reporting.
[0230] FIG. 42A to FIG. 42C illustrate the correspondence relation between
subframe number, the ULCC used for transmitting the PUSCH signal, and the
number of a DLCC for CSI reporting. In the example of FIG. 42A to FIG. 42C,
the terminal 200 can use the ULCC#1 and the ULCC#2 simultaneously to
transmit the PUSCH signal. Hie base station 100 decides in advance, and
notifies the terminal 200 in advance, that DLCCs for which reporting is possible
for the ULCC#1 are CC#1 to CC#3, and that DLCCs for which reporting is
possible for the ULCC#2 are CC#4 and CC#5, and similar. The base station
100 creates the correspondence relation between subframe number and DLCC
for which CSI reporting is performed as illustrated in FIG. 42A to FIG. 42C, and
notifies the terminal 200 in advance of this correspondence relation. In this
example, when the base station 100 is to cause CSI reporting for DLCC#5, the
ULCC for transmission of the PUSCH signal is set to CC#2, and the DCI format
0 PDCCH of this specification may be transmitted in subframe number "1" (or
"3", "5", or similar).
[0231] Examples of the configuration of the base station 100 and terminal
200 in the tenth embodiment can be implemented similarly to the fifth

embodiment (for example FIG. 23 and FIG. 24). FIG. 43 and FIG. 44 are
flowcharts illustrating an example of operation in the tenth embodiment. The
operation example is explained in the order of the step numbers, focusing
mainly on differences with the fifth embodiment.
[0232] First, when the base station 100 sets carrier aggregation, the base
station 100 sets the correspondence between the subframe number and DLCC
for CSI reporting. For example, the upper layer 140 sets the correspondence
relation as illustrated in FIG. 42A to FIG. 42C.
[0233] Then, the base station 100 transmits the correspondence relation
thus set, as control data, to the terminal 200 (S41), and the terminal 200
receives the control data and saves the correspondence relation (S42, S43).
For example, the upper layer 240 saves the correspondence relation. By this
means, the correspondence relation is shared between the base station 100 and
the terminal 200.
[0234] The base station 100 decides for which DLCC CSI reporting is to be
performed (Sll), and decides on the ULCC for transmitting the PUSCH signal
and the subframe number corresponding to the DLCC. For example, when CSI
reporting is to be performed for DLCC#5, the scheduler 110 decides on the
subframe number "1" and "carrier indicator" = ULCC#2 (in the case of cross-
carrier scheduling).
[0235] Thereafter, the base station 100 uses the specified subframe number
(and in the case of same-carrier scheduling, a specified DLCC as well), and
transmits the PDCCH signal for control information for uplink data including the
"CQI request" of "1" (S15).
[0236] The terminal 200 performs terminal-side processing (S92), and upon
receiving the PDCCH signal and detecting reception ("Y" in S450), detects
whether the "CQI request" is "1" (S271). When the "CQI request" is "1" ("Y" in
S271), the terminal 200 extracts the subframe number for which the PDCCH
signal is received and the information as to which ULCC is used to transmit the
PUSCH signal, based on the correspondence relation decides the DLCC for
reporting, and generates the CSI for this DLCC (S920). For example, the
PDCCH processing unit 223 extracts the "CQI request" and the information as

to which ULCC is to be used to transmit the PUSCH signal from the PDCCH
signal, and outputs the information to the CSI generation unit 224. The PDCCH
processing unit 223 uses the reception timing of subframe number "0" notified
in advance by the base station 100 as announcement information, and the
PDCCH signal reception timing, to extract the subframe number of the received
PDCCH signal, and outputs the subframe number to the CSI generation unit
224. The CSI generation unit 224 references the correspondence relation saved
in the upper layer 240 for the DLCC transmitting the PUSCH signal output from
the PDCCH processing unit 223 and the subframe number, acquires the
corresponding DLCC, and generates the CSI for this DLCC.
[0237] The terminal 200 transmits the generated CSI to the base station
100 as the PUSCH signal (S169). By receiving this, the base station 100 can
receive CSI for the specified DLCC (S17, S18).
[0238] Thus in the tenth embodiment also, the base station 100 can cause
reporting of the CSI for the specified DLCC based on the correspondence
relation between subframe number, the ULCC transmitting the PUSCH signal,
and the DLCC for CSI reporting. Hence in the tenth embodiment also, the base
station 100 can cause the terminal 200 to report the information relating to the
channel state of the arbitrary frequency band. Further, the terminal 200
reports the CSI for the specified DLCC based on the correspondence relation.
Hence compared with a case in which the terminal 200 performs CSI reporting
for all DLCCs, quantity of the information transmitted is reduced, so that
throughput can be improved. In the tenth embodiment also, after specifying
the DLCC for which CSI reporting is to be performed, the base station 100
transmits and receives signaling without newly increasing the number of bits.
Hence in the tenth embodiment, compared with for example the second
embodiment, there is no increase in control signaling overhead.
[0239] Eleventh Embodiment
Next, an eleventh embodiment is explained. Differences with the fifth
embodiment are mainly explained, and explanation of similar matter is omitted.
The eleventh embodiment is an example in which CSI reporting is performed

for the DLCC in an one-to-one relation with the ULCC which transmits the
PUSCH signal.
[0240] FIG. 45A to FIG. 45E illustrate an example of the correspondence
relation between the ULCC and DLCC. For example, the ULCC transmitting the
PUSCH signal and the DLCC for CSI reporting are associated in advance as in
FIG. 45A to FIG. 45E. For example, in the DCI format 0 PDCCH signal, ULCC#3
is specified as the ULCC for transmission of the PUSCH signal. In this case, it is
the DLCC#3 which is in the one-to-one relation with the ULCC#3, and so the
terminal 200 reports the CSI for DLCC#3. In order to cause CSI reporting of
the DLCC#3, the base station 100 sets the "CQI request" to "1", and transmits
the DQ format 0 PDCCH signal with ULCC#3 specified as the ULCC to transmit
the PUSCH signal. In the case of cross-carrier scheduling, the base station 100
can transmit this PDCCH signal from any DLCC. In the case of same-carrier
scheduling, the base station 100 uses the DLCC in the one-to-one
correspondence relation to transmit the PDCCH signal.
[0241] Examples of the configuration of the base station 100 and terminal
200 in the eleventh embodiment can be implemented similarly to the fifth
embodiment (for example FIG. 23 and FIG. 24). FIG. 46 and FIG. 47 are
flowcharts illustrating an example of operation in the eleventh embodiment.
The operation example is explained in the order of the step numbers, focusing
mainly on differences with the fifth embodiment.
[0242] First, the base station 100 sets carrier aggregation, and for example
generates the correspondence relation between ULCC and DLCC such as
illustrated in FIG. 45A to FIG. 45E (S100). For example, the upper layer 140
generates the correspondence relation.
[0243] The base station 100 notifies the terminal 200 of the setting
information, and the terminal 200 saves the setting information (S42, S43). For
example, the upper layer 240 saves the information, and also saves the
correspondence relation illustrated in FIG. 45A to FIG. 45E. The upper layer
240 may output the correspondence relation to the CSI generation unit 224. By
this means, the correspondence relation is shared by the base station 100 and
the terminal 200.

[0244] Then, the base station 100 decides for which DLCC CSI reporting is
to be performed, and decides the ULCC to transmit the PUSCH signal according
to this decision (S101). For example, the scheduler 110 acquires the
correspondence relation from the upper layer 140, and based on this
correspondence relation, decides the ULCC corresponding to the DLCC decided
on by the report CC decision unit 111. The base station 100 sets the "CQI
request" to "1", generates the PDCCH signal for the control information for
uplink data (for example DCI format 0) specifying the ULCC corresponding to
the DLCC for CSI reporting to transmit the PUSCH signal, and transmits the
PDCCH signal to the terminal 200 (S14, S15).
[0245] The terminal 200 receives the PDCCH signal through terminal-side
processing (S102), and detects whether the "CQI request" is "1" (S271). When
the "CQI request" is "1", based on the correspondence relation, the terminal
200 takes the DLCC corresponding to the ULCC transmitting the PUSCH signal
to be the DLCC for CSI reporting, and generates the CSI. For example, the
PDCCH processing unit 223 extracts the "CQI request" and the ULCC for
transmission of the PUSCH signal from the PDCCH signal, and outputs these to
the CSI generation unit 224. Based on the correspondence relation, the CSI
generation unit 224 takes the DLCC corresponding to the ULCC to be the DLCC
for CSI reporting, and generates the CSI.
[0246] Then, the terminal 200 transmits the CSI to the base station 100 as
the PUSCH signal (S169), and by receiving this, the base station 100 can
receive the CSI for the specified DLCC (S17, S18).
[0247] Thus, in the eleventh embodiment also, the base station 100 can
specify the DLCC for CSI reporting based on the correspondence relation
between the ULCC transmitting the PUSCH signal and the DLCC for CSI
reporting. Hence in the eleventh embodiment also, the base station 100 can
cause the terminal 200 to report the information relating to the channel state of
the arbitrary frequency band. Further, based on the correspondence relation,
the terminal 200 reports the CSI for the specified DLCC. Hence compared with
a case in which the terminal 200 performs CSI reporting for all DLCCs, the
quantity of information transmitted is reduced, so that throughput can be

improved. In the eleventh embodiment also, after specifying the DLCC for
which CSI reporting is to be performed, the base station 100 transmits and
receives signaling without newly increasing the number of bits. Hence in the
eleventh embodiment, compared with for example the second embodiment,
there is no increase in control signaling overhead.
[0248] Twelfth Embodiment
Next, a twelfth embodiment is explained. The twelfth embodiment is an
example in which, when performing CSI reporting for the DLCC in an inactive
state, reporting is caused to occur with a transmission timing slower by a
constant time.
[0249] FIG. 48A to FIG. 48C illustrate an example of report timing. As
explained in the second embodiment, the CC has for example an active state
and the inactive state. When CSI reporting is caused for the DLCC in the
inactive state, compared with the DLCC in the active state, a constant time is
required until the CSI is generated. This is because the terminal 200 may halt
reception processing of the DLCC in the inactive state, and may not be
measuring the CSI of the DLCC in the inactive state. In such a case, the
reporting timing is delayed to for example from four subframes later to six
subframes later. By thus delaying the reporting timing for the DLCC in the
inactive state, time is secured until the terminal 200 is in the active state and
measurements of CQI and similar for the DLCC are started.
[0250] The twelfth embodiment can be applied to systems explained in the
first to eleventh embodiments. Further, the twelfth embodiment can also be
applied to the thirteenth to fifteenth embodiments described below. For
example, when the upper layer 140 sets carrier aggregation, the report timing
of the DLCC in the inactive state may be set to for example "transmission six
subframes after PDCCH signal reception" or similar, and the terminal 200 may
be notified of this setting. Or, the timing may be set in advance as a parameter
determined in advance within the system. The upper layer 240 of the terminal
200 saves this setting, and the information is shared between the base station
100 and the terminal 200. For example, when the base station 100 transmitts
the DCI format 0 PDCCH signal (second embodiment) with the "CQI request"

set to "11000", the terminal 200 transmits the CSI for the DLCC#2, in the
inactive state, after six subframes.
[0251] The timing for transmission of the CSI of the DLCC in the inactive
state need only be delayed from the timing for transmission of the DLCC in the
active state, and in addition to six subframes, a delay of five subframes, eight
subframes, or similar may be used.
[0252] Thirteenth Embodiment
Next, a thirteenth embodiment is explained. Differences with the second
and fifth embodiments are mainly explained, and explanation of similar matter
is omitted. The thirteenth embodiment is an example in which a MAC CE
(Media Access Control Control Element), which is a control packet, is also used
to start aperiodic CSI reporting.
[0253] FIG. 49 illustrates an example of the DLCC for CSI reporting. The
base station 100 transmits the MAC CE to the terminal 200 in order to change
the DLCC in the inactive state (a deactivated DL CC) into the DLCC in the active
state (the activated DL CC). Upon receiving the MAC CE, the terminal 200 puts
the DL CC specified by the MAC CE into the active state, generates the CSI for
the DLCC entered the active state, and transmits the CSI to the base station
100. In the example of FIG. 49, the base station 100 transmits to the terminal
200 the MAC CE specifying the DLCC#5, and the terminal 200 puts the DLCC#5
into the active state, generates the CSI for the DLCC#5, and transmits the CSI
to the base station 100.
[0254] Examples of the configuration of the base station 100 and terminal
200 in the thirteenth embodiment can be implemented similarly to the fifth
embodiment (for example FIG. 23 and FIG. 24). FIG. 50 is a sequence diagram
illustrating an example of operation in the thirteenth embodiment. The
operation example is explained in the order of the step numbers, focusing
mainly on differences with the fifth embodiment.
[0255] First, the base station 100 sets carrier aggregation (S110). For
example, the upper layer 140 sets each DLCC as the CC in the inactive state
("Configured but Deactivated CC"), the CC in the active state ("Configured and
Activated CC"), or the PDCCH monitoring set CC ("PDCCH monitoring set"). For

example, the upper layer 140 saves the setting information. The base station
100 then transmits this setting information to the terminal 200 as the PDSCH
signal (S41).
[0256] The terminal 200 receives the PDSCH signal and saves the setting
information (S42, S43). For example, the upper layer 240 saves the setting
information. By this means, the base station 100 and terminal 200 share the
information as to which DLCC is in the active state, which is in the inactive state,
and which is CC in the PDCCH monitoring set in the active state.
[0257] The base station 100 decides which DLCC is to be put into the active
state, of the DLCCs in the inactive state (Sill). For example, based on setting
information saved by the upper layer 140, whether the DLCC is to be put into
the active state is decided. This decision is also used by the base station 100 to
determine for which DLCC the CSI is to be reported.
[0258] Next, the base station 100 generates the MAC CE (or MAC CE for CC
Management), which is the control packet (S112). For example, the upper
layer 140 decides on the DLCC to put into the active state (and a DLCC for CSI
reporting), and generates the MAC CE specifying the DLCC thus decided.
[0259] Next, the base station 100 transmits the generated MAC CE (SI 13).
For example, the upper layer 140 outputs the generated MAC CE to the PDSCH
generation unit 114, and the MAC CE is transmitted as the PDSCH signal.
[0260] Upon receiving the PDSCH signal (SI 14), the terminal 200 transmits
an ACK signal to the base station 100 (S115). For example, the PDSCH
processing unit 225 extracts an information included in the MAC CE from the
PDSCH signal, and outputs a signal indicating the success of extraction to the
ACK/NACK generation unit 226. Upon input of this signal, the ACK/NACK
generation unit 226 generates the ACK signal, and outputs the ACK signal to
the PUCCH generation unit 230. For example, the ACK signal is transmitted to
the base station 100 as the PUCCH signal.
[0261] Upon receiving the ACK signal (S116), the base station 100 puts the
DLCC specified by the MAC CE into the active state (activates the DLCC) (SI 17).
For example, the upper layer 140 resets the DLCC, which is set in the inactive
state, into the active state, and saves the setting as setting information.

Further, the upper layer 140 transmits the signal in the frequency bandwidth of
the DLCC in the active state, or similar, to each unit.
[0262] On the other hand, the terminal 200 puts the DLCC specified by the
MAC CE into the active state (SI 18). For example, the upper layer 240 inputs
the information included in the MAC CE from the PDSCH processing unit 225,
and registers information relating to the DLCC put into the active state of this
information as the active state. For example, the upper layer 240 sets each
unit such that the signal in the frequency band of the specified DLCC is received,
and similar.
[0263] Next, the terminal 200 generates the CSI for the DLCC specified by
the MAC CE (S119). For example, the upper layer 240 outputs the information
on the DLCC put into the active state to the CSI generation unit 224. The CSI
generation unit 224 generates the CSI for the corresponding DLCC based on
this information.
[0264] Next, the terminal 200 transmits the generated CSI as the PUSCH
signal (S120, S121), and the base station 100, by receiving this signal, receives
the CSI for the DLCC put into the active state (S17, S18).
[0265] Thus in the thirteenth embodiment also, the base station 100, by
using the MAC CE to specify the DLCC to be put into the active state, can
receive CSI for the DLCC. Hence in the thirteenth embodiment also, the base
station 100 can cause the terminal 200 to report the information relating to the
channel state of the arbitrary frequency band. Further, the terminal 200
reports the CSI for the DLCC put into the active state. Hence compared with a
case in which the terminal 200 performs CSI reporting for all DLCCs,
throughput can be improved.
[0266] Fourteenth Embodiment
Next, a fourteenth embodiment is explained. Differences with the fifth and
ninth embodiments are mainly explained, and explanation of similar matter is
omitted. The fourteenth embodiment is an example which combines the fifth
embodiment and the ninth embodiment.
[0267] In the fifth embodiment, for example, based on the correspondence
relation between the PDCCH monitoring CC and scheduled DLCC, the base

station 100 uses a certain PDCCH monitoring CC to transmit the PDCCH signal
for control information for uplink data (fr example DCI format 0) in which "CQI
request" is set to "1". The terminal 200 reports the CSI for all scheduled DLCCs
in the correspondence relation with the PDCCH monitoring CC (for example FIG.
22AandFIG. 22B).
[0268] In the ninth embodiment, in the PDCCH signal for control
information for uplink data (for example DCI format 0) in which the "CQI
request" is set to "1", the "carrier indicator" is used to specify the DLCC for CSI
reporting (for example FIG. 38A and FIG. 38B).
[0269] FIG. 51A and FIG. 51B illustrate examples of the DLCC for CSI
reporting and ULCC used in transmission, respectively. In the fourteenth
embodiment, the number of scheduled DLCCs which can be associated with the
PDCCH monitoring CC is three or fewer. In the example of FIG. 51A, DLCC#1
and DLCC#4 are set as PDCCH monitoring CCs, and the scheduled DLCC
associated with DLCC#1, which is the PDCCH monitoring CC, are DLCC#1 to #3
(first group). DLCCs associated with DLCC#4, which is a PDCCH monitoring CC,
are DLCC#4 to #6 (second group).
[0270] In the fourteenth embodiment also, when "CQI request" is set to "1",
"carrier indicator" is used to specify the DLCC for CSI reporting. For example 3
bits can be used in the "carrier indicator", and so in the first group, for example,
when causing CSI reporting for DLCC#2 and DLCC#3, the base station 100 can
set the "carrier indicator" to "011". That is, when causing CSI reporting for
DLCC#2 and DLCC#3, the base station 100 uses the DLCC#1 which is the
PDCCH monitoring CC, and transmits the DCI format 0 PDCCH signal in which
the "CQI request" is set to "1" and the "carrier indicator" is set to "Oil".
[0271] At this time, similarly to the ninth embodiment, the base station 100
cannot use the "carrier indicator" to specify the ULCC to transmit the PUSCH
signal. Hence in this case the ULCC to transmit the PUSCH signal is decided in
advance for each PDCCH monitoring CC (each group), and the ULCC is used for
CSI transmission. In the example of FIG. 51B, the CSI report (the CSI for
DLCC#1 to DLCC#3) started by the PDCCH transmitted using the PDCCH
monitoring CC#1 (DLCC#1) is transmitted by the ULCC#1 as the PUSCH signal.

[0272] Examples of the configuration of the base station 100 and terminal
200 in the fourteenth embodiment can be implemented similarly to the fifth and
ninth embodiments (for example FIG. 23 and FIG. 24). FIG. 52 and FIG. 53 are
sequence diagrams illustrating an example of operation in the fourteenth
embodiment. The operation example is explained in the order of the step
numbers, focusing mainly on differences with the fifth and ninth embodiments.
[0273] First, when setting carrier aggregation, the base station 100 sets the
correspondence relation between the PDCCH monitoring CC and scheduled CC,
and sets the ULCC for aperiodic CSI reporting (S120). For example, the upper
layer 140 decides the scheduled DLCC (three or fewer) to be in the same group
as the DLCC which is the PDCCH monitoring CC, as illustrated in FIG. 51A.
Further, the upper layer 140 decides on one ULCC for aperiodic CSI
transmission in each group. The upper layer 140 saves the information thus
decided as setting information, and notifies the terminal 200 (S41).
[0274] TTie terminal 200 receives the setting information as the PUSCH
signal, and saves the setting information (S43). For example, the upper layer
240 saves the setting information.
[0275] Then, upon deciding for which DLCC CSI reporting is to be
performed, the base station 100 decides on the DLCC which is the PDCCH
monitoring CC to transmit the PDCCH signal based on the setting information.
Further, the base station 100 generates the "carrier indicator" specifying the
combination of DLCCs for CSI reporting (S121). For example, when the report
CC decision unit 111 decides on DLCC#2 for CSI reporting, the scheduler 110
acquires the setting information from the upper layer 140, and decides on
transmission using the DLCC#1, which is a PDCCH monitoring CC. Further, the
scheduler 110 decides to set "CQI request" to "1" and "carrier indicator" to
"010".
[0276] Next, the base station 100 generates the control information for
uplink data (for example DCI format 0) (S13). For example, the scheduler 110
generates the control information with the "CQI request" set to "1" and the
"carrier indicator" set to "010", and outputs the control information to the
PDCCH generation unit 113.

[0277] Then, the base station 100 uses the decided-upon DLCC which is the
PDCCH monitoring CC to transmit the PDCCH signal to the terminal 200 (S14,
S15). The base station 100 can use a plurality of PDCCH monitoring CCs to
specify DLCCs for CSI reporting. For example, in the example of FIG. 51A, the
two PDCCH monitoring CCs which are DLCC#1 and DLCC#4 are used to specify
DLCCs for CSI reporting.
[0278] Through terminal-side processing (S122), the terminal 200 receives
the PDCCH signal, and detects DCI format 0 and detects "CQI request" = "1"
("Y" in S450, "Y" in S271).
[0279] Next, the terminal 200 extracts the "carrier indicator" from the DCI
format 0 PDCCH signal with the "CQI request" set to "1", and generates the CSI
for the DLCC specified by the "carrier indicator" (S1220). For example, the
PDCCH processing unit 223 reads out the "CQI request" and "carrier indicator"
from the PDCCH signal, and outputs these to the CSI generation unit 224. The
PDCCH processing unit 223 identifies the DLCC from the reception frequency
bandwidth of the received PDCCH signal (the DLCC which is a PDCCH
monitoring CC), and outputs the DLCC information to the CSI generation unit
224. The CSI generation unit 224 acquires setting information from the upper
layer 240 and acquires the corresponding DLCC from the DLCC information and
"carrier indicator" from the PDCCH processing unit 223 based on the setting
information. The CSI generation unit 224 generates CSI for the acquired DLCC.
In this case, when the PDCCH signal has been transmitted using the plurality of
PDCCH monitoring CCs, CSI is generated for each.
[0280] Then, the terminal 200 uses the ULCC decided in advance to
transmit the generated CSI to the base station 100 (S169). For example, the
PUSCH generation unit 229 acquires a setting information from the upper layer
240, and extracts an information as to which ULCC is to be used for
transmission. The PUSCH generation unit 229 then uses the extracted ULCC to
output the PUSCH signal so as to be transmitted.
[0281] The base station 100 receives the PUSCH signal, and receives the
CSI for the specified DLCC (S17, S18).

[0282] Thus in the fourteenth embodiment also, similarly to the fifth and
ninth embodiments, the DLCC for CSI reporting can be specified by a
combination of the PDCCH monitoring CC and "carrier indicator". Hence in the
fourteenth embodiment also, the base station 100 can cause the terminal 200
to report information relating to the channel state of the arbitrary frequency
band. Further, based on the correspondence relation, the terminal 200 reports
the CSI of the DLCC specified by the combination of the PDCCH monitoring CC
and "carrier indicator". Hence compared with a case in which the terminal 200
performs CSI reporting for all DLCCs, the quantity of information transmitted is
reduced, so that throughput can be improved.
[0283] Further, in the fourteenth embodiment, even when the number of
DLCCs is greater than three, a combination of arbitrary DLCCs for CSI reporting
can be specified by combining into a plurality of groups. In the above-
described example, six DLCCs are grouped into two groups. When there are
eight DLCCs, for example, grouping into three groups is possible. As described
above, by using the plurality of PDCCH monitoring CCs to transmit the PDCCH
signal, the base station 100 can cause CSI reporting to be performed for DLCCs
in different groups.
[0284] Fifteenth Embodiment
Next, a fifteenth embodiment is explained. Differences with the second
embodiment are mainly explained, and explanation of similar matter is omitted.
The fifteenth embodiment is an example in which, in a control information for
uplink data supporting SU-MIMO (control information relating to PUSCH), a
portion of fields in the control information is used to specify the DLCC for CSI
reporting.
[0285] In a radio communication system, SU-MIMO (Single User-MIMO) can
be supported in the uplink. On the other hand, in the above-described second
embodiment and similar, the DCI format 0 is explained as the control
information for uplink data transmission, but in order to support SU-MIMO, a
DCI format can be newly defined. SU-MIMO enables transmission and
reception of different signals by one user (the terminal 200) and one base
station 100, each using the plurality of antennas, for each antenna directionality.

[0286] FIG. 54A illustrates an example of parameters of a DCI format
supporting SU-MIMO. The SU-MIMO for uplinks supports transmission of a
maximum two data blocks (also called transport blocks) using the plurality of
antennas. In the example of FIG. 54A, the "NDI" (New Data Indicator) field
and the "MCS and RV" (Modulation and Coding Scheme and Redundancy
Version) field are fields defined for two data blocks, so as to correspond to two
data blocks.
[0287] In the fifteenth embodiment, when the "CQI request" is set to "1"
(when aperiodic CSI reporting is performed), one of the two data blocks in the
"NDI" field and the "MCS and RV" field is made valid, and the other is used to
specify the DLCC for aperiodic CSI reporting.
[0288] FIG. 54B is used to explain an example of a case in which such the
Da format is specified. For example, the base station 100 sets the "CQI
request" to "1", and uses the six bits in total of the "NDI" field and the "MCS
and RV" field for the second transport block to specify the DLCC for CSI
reporting. By means of this specification, the terminal 200 generates and
transmits to the base station 100 the CSI for the specified DLCC. This "six bits"
is one example, and bits specified as the "NDI" field and the "MCS and RV" field
may be used. Also, instead of the second transport block, the two fields for the
first transport block may be used.
[0289] FIG. 55 and FIG. 56 illustrate examples of the configuration of the
base station 100 and the terminal 200 respectively of the fifteenth embodiment.
[0290] The base station 100 further includes two antennas 121 and 122,
two radio reception units 130-1 and 130-2, and a multi-antenna reception
processing unit 150. The two radio reception units 130-1 and 130-2 and the
multi-antenna reception processing unit 150 are for example included in the
reception unit 12 in the first embodiment.
[0291] The two antennas 121 and 122 each receive radio signals
transmitted by MIMO from the terminal 200, and output signals to the two
radio reception units 130-1 and 130-2 respectively.

[0292] The two radio reception units 130-1 and 130-2 each down-convert
the received radio signals, converting the signals into baseband signals, and
output the signals to the multi-antenna reception processing unit 150.
[0293] The multi-antenna reception processing unit 150 performs a
precoding matrix operation and similar, for example, and outputs baseband
signal so as to correspond to the distribution (or weighting) when transmitted
from the terminal 200 to the two antennas.
[0294] The terminal 200 further includes two antennas 211 and 212, two
radio transmission units 232-1 and 232-2, and a multi-antenna transmission
processing unit 250. The two radio transmission units 232-1 and 232-2 and the
multi-antenna transmission processing unit 250 are for example included in the
transmission unit 22 in the first embodiment.
[0295] The multi-antenna transmission processing unit 250 performs
precoding matrix and similar operations on the baseband signal output from the
multiplexing unit 231, and outputs the result. By this means, the radio signal is
transmitted from for example the two antennas 211 and 212 according to a
precoding matrix or other distribution.
[0296] The two radio transmission units 232-1 and 232-2 perform up-
conversion by frequency conversion or similar of the baseband signals output
from the multi-antenna transmission processing unit 250, and generate radio
signals respectively. The two radio transmission units 232-1 and 232-2 output
the generated radio signals to the two antennas 211 and 212 respectively.
[0297] The two antennas 211 and 212 each transmit the radio signals to the
base station 100.
[0298] Next, an example of operation is explained. FIG. 57 and FIG. 58 are
flowcharts illustrating an operation example. The operation example is
explained in the order of the step numbers, focusing mainly on differences with
the second embodiment.
[0299] The base station 100, upon deciding for which DLCC CSI reporting is
to be performed, accordingly decides parameter value to be transmitted using
the "MCS and RV for 2nd TB" field and the "NDI for 2nd TB" field (S130). For
example, the scheduler 110 generates parameter value corresponding to the

DLCC for CSI reporting decided on by the report CC decision unit 111. Similarly
to the second embodiment, the scheduler 110 can specify a combination of the
plurality of DLCCs.
[0300] Then, the base station 100 generates the control information for
uplink data (hereafter, control information for uplink MIMO) in a new DCI
format (for example FIG. 54A), and transmits the PDCCH signal for control
information for uplink MIMO to the terminal 200 (S13 to S15).
[0301] The terminal 200, upon receiving the PDCCH signal through terminal-
side processing (S131), detects whether the PDCCH signal for control
information for uplink MIMO is received (S1310). For example, the PDCCH
processing unit 223 detects the PDCCH signal for control information for uplink
MIMO from the signal length.
[0302] When the terminal 200 cannot detect the PDCCH signal for control
information for uplink MIMO ("N" in S1310), the terminal 200 determines that
the base station 100 is not requesting aperiodic CSI reports, and ends the
series of processing.
[0303] On the other hand, upon detecting the PDCCH signal for control
information for uplink MIMO ("Y" in S1310), the terminal 200 determines
whether the "CQI request" is "1" (S271). When the "CQI request" is "1" (when
aperiodic CSI reporting is requested) ("Y" in S271), the terminal 200 generates
the CSI for the DLCC corresponding to the parameter values transmitted in the
"MCS and RV for 2nd TB" field and the "NDI for 2nd TB" field (S1311). For
example, the PDCCH processing unit 223 extracts the parameter values of the
"MCS and RV for 2nd TB" and "NDI for 2nd TB" from the PDCCH signal, and
outputs the values together with the "CQI request" to the CSI generation unit
224. The CSI generation unit 224 generates the CSI for the corresponding
DLCC based on the parameter values.
[0304] Then, the terminal 200 transmits the generated CSI as the PUSCH
signal (S169). The base station 100 receives the PUSCH signal, and so can
receive the CSI generated by the terminal 200 (S17, S18).
[0305] In the fifteenth embodiment also, the base station 100 can specify
the DLCC for CSI reporting through the control information for uplink MIMO, so

that the base station 100 can cause the terminal 200 to report the information
relating to the channel state of the arbitrary frequency band. Further, the
terminal 200 reports the CSI for the specified DLCC. Hence compared with a
case in which the terminal 200 performs CSI reporting for all DLCCs, the
quantity of information transmitted is reduced, so that throughput can be
improved.
[0306] In the fifteenth embodiment, an example is explained in which, when
specifying the DLCC for CSI reporting, the two fields "NDI" and "MCS and RV"
are used. In the new DCI format, for example, another field may be used to
specify the DLCC for CSI reporting. In this case, a field not illustrated in FIG.
54A can be used for specification. If parameter values of fields capable of
transmitting together with "CQI request" are used, the DLCC for CSI reporting
can be specified.
[0307] Other Examples
For example, in the explanation of the second embodiment, when the
terminal includes one or more "l"'s in the "CQI request", the CSI for the
specified DLCC is generated, and user data is also generated (for example S166
in FIG. 11). However, the terminal 200 may for example generate the CSI for
the specified DLCC without generating user data. In each of the third and
subsequent embodiments also, the terminal 200 can generate the specified
DLCC without generating user data (for example S166 in FIG. 17 and similar).
EXPLANATION OF REFERENCE NUMERALS
[0308] 100 RADIO BASE STATION APPARATUS (BASE STATION)
110 SCHEDULER
111 REPORT CC DECISION UNIT

113 PDCCH GENERATION UNIT
114 PDSCH GENERATION UNIT
120 (121, 122) ANTENNA
140 UPPER LAYER
200 TERMINAL APPARATUS (TERMINAL)
222 MEASUREMENT UNIT
223 PDCCH PROCESSING UNIT

224 CSI GENERATION UNIT
225 PDSCH PROCESSING UNIT
227 CSI PROCESSING UNIT
229 PUSCH GENERATION UNIT
235 SEPARATION UNIT
240 UPPER LAYER

We Claim:
1. A radio communication method for performing radio communication by
using a plurality of frequency bands in a first radio communication apparatus
and a second radio communication apparatus, the method comprising:
transmitting to the second radio communication apparatus a first channel
state information request corresponding to each of the plurality of frequency
band, by the first radio communication apparatus; and
transmitting to the first radio communication apparatus an information
relating to a channel state for the frequency band specified by the first channel
state information request, when the second radio communication apparatus
receives the first channel state information request, by the second radio
communication apparatus .
2. The radio communication method according to Claim 1, wherein the first
radio communication apparatus transmits the first channel state information
request by using a second radio resource configured to be used in data signal
transmission.
3. The radio communication method according to Claim 1, wherein the first
radio communication apparatus groups the plurality of frequency bands into a
plurality of groups, and transmits to the second radio communication apparatus
for each of the groups the first channel state information request corresponding
to each of the plurality of frequency bands included in each of the groups.
4. The radio communication method according to Claim 1, wherein the first
radio communication apparatus transmits a control information to be used
when the second radio communication apparatus transmits the information
relating to the channel state to the first radio communication apparatus, and
the first channel state information request.
5. The radio communication method according to Claim 2, further
comprising:

transmitting a second channel state information request by using a first
radio resource configured to be used in control signal transmission to the
second radio communication apparatus, by the first radio communication
apparatus transmits, wherein
the second radio communication apparatus transmits the information
relating to the channel state for the frequency band specified by the first
channel state information request transmitted by using the second radio
resource, when the second radio communication apparatus receives the second
channel state information request to request the information relating to the
channel state.
6. The radio communication method according to Claim 2, further
comprising:
transmitting to the second radio communication apparatus a second
channel state information request by using a first radio resource configured to
be used in control signal transmission, wherein
the second radio communication apparatus receives a control information
transmitted with the second channel state information request using by the first
radio resource, as a control information used when the second radio
communication apparatus receives a data signal transmitted from the first radio
communication apparatus to the second radio communication apparatus, and
transmits to the first radio communication apparatus an information relating to
the channel state by using the control information received with the first
channel state information request by using the second radio resource, when the
second communication apparatus receives the second channel state information
request requesting the information relating the channel state.
7. A radio communication method for performing radio communication by
using a plurality of frequency bands in a first radio communication apparatus
and a second radio communication apparatus, the method comprising:

transmitting to the second radio communication apparatus a first channel
state information request by using a first frequency band of the plurality of
frequency bands, by the first radio communication apparatus; and
transmitting to the first radio communication apparatus an information
relating to a channel state for a frequency band in a correspondence with the
first frequency band, when the second radio communication apparatus receives
the first channel state information request, by the second radio communication
apparatus .
8. The radio communication method according to Claim 7, wherein the
second radio communication apparatus transmits to the first radio
communication apparatus the information relating to the channel state for a
frequency band for which scheduling is possible by using a control information
received with the first channel state information request by using the first
frequency band.
9. The radio communication method according to Claim 8, further
comprising:
transmitting to the second radio communication apparatus an
information indicating correspondence relation between the frequency band for
which scheduling is possible and the first frequency band, by the first radio
communication apparatus, wherein
the second radio communication apparatus transmits the information
relating to the channel state for the frequency band for which scheduling is
possible according to the information indicating the correspondence relation.
10. The radio communication method according to Claim 7, further
comprising:
transmitting the information indicating the correspondence relation to
the second radio communication apparatus, by the first radio communication
apparatus, wherein

the second radio communication apparatus transmits the information
relating to the channel state of a frequency band in a correspondence with the
first frequency band according to the information indicating the correspondence
relation.
11. A radio communication method for performing radio communication by
using a plurality of frequency band in a first radio communication apparatus
and a second radio communication apparatus, the method comprising:
transmitting a first channel state information request to the second radio
communication apparatus, by the first radio communication apparatus; and
transmitting an information relating to a channel state for a frequency
band in a correspondence with a first frequency band of the plurality of
frequency bands to the first radio communication apparatus by using the first
frequency band, when the second communication apparatus receives the first
channel state information request, by the second radio communication
apparatus.
12. The radio communication method according to Claim 11, wherein the
first radio communication apparatus transmits to the second radio
communication apparatus the first channel state information request and a
control information indicating the first frequency band.
13. The radio communication method according to Claim 11, wherein the
first frequency band indicate same identification number as a frequency band
used in transmission of the first channel state information request.
14. The radio communication method according to Claim 11, further
comprising:
transmitting to the second radio communication apparatus an
information indicating the correspondence relation between the first frequency
band and frequency band for which an information relating to the channel state
is transmitted, by the first radio communication apparatus, wherein

the second radio communication apparatus transmits the information
relating to the channel state according to the information indicating the
correspondence relation.
15. The radio communication method according to Claim 11, wherein the
correspondence relation is a one-to-one correspondence relation between the
first frequency band and the frequency band for which the information relating
to the channel state is transmitted.
16. A radio communication method for performing radio communication by
using a plurality of frequency bands in a first radio communication apparatus
and a second radio communication apparatus, the method comprising:
transmitting a first channel state information request to the second radio
communication apparatus, by the first radio communication apparatus; and
transmitting to the first radio communication apparatus an information
relating to a channel state for one frequency band of the plurality of frequency
bands, specified by the first channel state information request, when the
second communication apparatus receives the first channel state information
request, by the second radio communication apparatus.
17. The radio communication method according to Claim 16, further
comprising:
transmitting a second channel state information request and the first
channel state information request to the second radio communication apparatus,
by the first radio communication apparatus, wherein
the second radio communication apparatus transmits the information
relating to the channel state for the frequency band specified by the first
channel state information request, when the second radio communication
apparatus receives the second channel state information request requesting the
information relating to the channel state.

18. A radio communication method for performing radio communication by
using a plurality of frequency bands in a first radio communication apparatus
and a second radio communication apparatus, the method comprising:
transmitting a carrier indicator as a first channel state information
request to the second radio communication apparatus, and transmitting a
second channel state information request to the second radio communication
apparatus, by the first radio communication apparatus; and
transmitting an information relating to a channel state for a frequency
band specified by the carrier indicator received as the first channel state
information request to the first radio communication apparatus by using a
frequency band determined in advance, when the second communication
apparatus receives the second channel state information request requesting
information relating to the channel state, by the second radio communication
apparatus
19. The radio communication method according to Claim 18, further
comprising:
transmitting data signal to the first radio communication apparatus by
using the frequency band specified by the carrier indicator, when the second
communication apparatus receives the second channel state information
request not requesting information relating to the channel state, by the second
radio communication apparatus.
20. A radio communication method for performing radio communication by
using a plurality of frequency bands in a first radio communication apparatus
and a second radio communication apparatus, the method comprising:
transmitting a first channel state information request to the second radio
communication apparatus, by the first radio communication apparatus; and
transmitting to the first radio communication apparatus an information
relating to a channel state for a frequency band in a correspondence with
subframe number with which the first channel state information request is
transmitted, when the second radio communication apparatus receives the first

channel state information request, by the second radio communication
apparatus.
21. The radio communication method according to Claim 20, further
comprising:
transmitting to the second radio communication apparatus an
information indicating a correspondence relation between the subframe number
and the frequency band for which the information relating to the channel state
is transmitted, by the first radio communication apparatus, wherein
the second radio communication apparatus transmits the information
relating to the channel state according to the information indicating the
correspondence relation.
22. The radio communication method according to Claim 20, wherein the
second radio communication apparatus transmits the information relating to the
channel state for the frequency band in a correspondence with a frequency
band specified by a carrier indicator and the subframe number by using the
frequency band specified by the carrier indicator.
23. A radio communication method for performing radio communication by
using a plurality of frequency bands in a first radio communication apparatus
and a second radio communication apparatus, the method comprising:
transmitting to the second communication apparatus a control packet
causing a frequency band in an inactive state of the plurality of frequency
bands to change an active state, by the first radio communication apparatus;
and
changing the frequency band in the inactive state to the active state,
and transmitting to the first radio communication apparatus an information
relating to a channel state of the frequency band in the active state, when the
second radio communication apparatus receives the control packet, by the
second radio communication apparatus.

24. A radio communication method for performing radio communication by
using a plurality of frequency bands in a first radio communication apparatus
and a second radio communication apparatus, the method comprising:
transmitting to the second radio communication apparatus a carrier
indicator by using a first frequency band of the plurality of frequency band, and
transmitting to the second radio communication apparatus a first channel state
information request, by the first radio communication apparatus; and
transmitting to the first radio communication apparatus an information
relating to a channel state for a frequency band specified by the carrier
indicator and corresponded with the first frequency band, when the second
radio communication apparatus receives the first channel state information
request requesting the information relating to the channel state, by the second
radio communication apparatus.
25. The radio communication method according to Claim 24, wherein the
carrier indicator can specify all combinations of frequency bands in
correspondence with the first frequency band.
26. A radio communication method for performing radio communication by
using a plurality of frequency bands in a first radio communication apparatus
and a second radio communication apparatus, the method comprising:
transmitting to the second radio communication apparatus a control
information for a first data block of control information for MIMO
communication as a first channel state information request corresponding to
each of the plurality of frequency band, and transmitting to the second radio
communication apparatus a second channel state information request, by the
first radio communication apparatus; and
transmitting to the first radio communication apparatus an information
relating to a channel state for the frequency band specified by the first channel
state information request, when the second radio communication apparatus
receives the second channel state information request requesting the

information relating to the channel state, by the second radio communication
apparatus.
27. The radio communication method according to any one of Claims 1, 7,
11,16,18, 20, 24 and 26, wherein the first radio communication apparatus
transmits the first channel state information request by using a first radio
resource configured to be used in control signal transmission.
28. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a transmission unit which transmits a first channel state information
request corresponding to each of the plurality of frequency band; and
a reception unit which receives from the other radio communication
apparatus an information relating to a channel state for the frequency band
specified by the first channel state information request.
29. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a reception unit which receives from the another radio communication
apparatus a first channel state information request corresponding to each of the
plurality of frequency band; and
a transmission unit which transmits to the another radio communication
apparatus an information relating to a channel state for the frequency band
specified by the first channel state information request.
30. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:

a transmission unit which transmits to the another radio communication
apparatus a first channel state information request by using a first frequency
band of the plurality of frequency bands; and
a reception unit which receives from the another radio communication
apparatus an information relating to a channel state for a frequency band in a
correspondence with the first frequency band.
31. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a reception unit which receives a first channel state information request
transmitted by using a first frequency band of the plurality of frequency bands;
and
a transmission unit which transmits to the another radio communication
apparatus an information relating to a channel state for a frequency band in a
correspondence with the first frequency band.
32. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a transmission unit which transmits a first channel state information
request to the another radio communication apparatus; and
a reception unit which receives from the another radio communication
apparatus an information relating to a channel state for a frequency band in a
correspondence with a first frequency band of the plurality of frequency bands,
wherein the reception unit receives the information relating to the
channel state transmitted by using the first frequency band.
33. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:

a reception unit which receives a first channel state information request
from the another radio communication apparatus; and
a transmission unit which transmits an information relating to a channel
state for a frequency band in a correspondence with a first frequency band of
the plurality of frequency bands to the another radio communication apparatus
by using the first frequency band.
34. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a transmission unit which transmits to the another radio communication
apparatus a first channel state information request specifying one frequency
band of the plurality of frequency bands; and
a reception unit which receives from the another radio communication
apparatus an information relating to a channel state for the one specified
frequency band.
35. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a reception unit which receives a first channel state information request
from the another radio communication apparatus; and
a transmission unit which transmits to the another radio communication
apparatus an information relating to a channel state for one frequency band
specified by the first channel state information request, of the plurality of
frequency bands.
36. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a transmission unit which transmits a carrier indicator as a first channel
state information request to the another radio communication apparatus, and

further transmits to the another radio communication apparatus a second
channel state information request requesting an information relating to a
channel state; and
a reception unit which receives from the another radio communication
apparatus the information relating to the channel state for a frequency band
specified by the carrier indicator,
wherein the reception unit receives the information relating to the
channel state transmitted by using a frequency band determined in advance.
37. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a reception unit which receives a carrier indicator as a first channel state
information request from the another radio communication apparatus, and
receives a second channel state information request from the other radio
communication apparatus;
a transmission unit which transmits an information relating to a channel
state for a frequency band specified by the carrier indicator to the another radio
communication apparatus by using a frequency determined in advance, when
the reception unit receives the second channel state information request
requesting the information relating to the channel state.
38. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a transmission unit which transmits a first channel state information
request to the another radio communication apparatus; and
a reception unit which receives from the another radio communication
apparatus an information relating to a channel state for a frequency band in a
correspondence with number of subframe transmitting the first channel state
information.

39. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a reception unit which receives a first channel state information request
from the another radio communication apparatus; and
a transmission unit which transmits an information relating to a channel
state for a frequency band in a correspondence with subframe number
transmitting the first channel state information request to the other radio
communication apparatus.
40. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a transmission unit which transmits to the another radio communication
apparatus a control packet causing a frequency band in an inactive state of the
plurality of frequency band to change a frequency band an active state; and
a reception unit which receives from the another radio communication
apparatus an information relating to a channel state for the frequency band
changed from the inactive state to the active state.
41. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a reception unit which receives from the another radio communication
apparatus a control packet causing a frequency band in an inactive state of the
plurality of frequency bands to change a frequency band in an active state; and
a transmission unit which transmits to the another radio communication
apparatus an information relating to a channel state for the frequency band
changed from the inactive state to the active state.

42. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a transmission unit which transmits a carrier indicator by using a first
frequency band of the plurality of frequency bands to the another radio
communication apparatus, and transmits a first channel state information
request requesting an information relating to a channel state to the another
radio communication apparatus; and
a reception unit which receives from the another radio communication
apparatus the information relating to the channel state for a frequency band
specified by the carrier indicator and corresponded with the first frequency
band.
43. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a reception unit which receives from the another radio communication
apparatus a carrier indicator transmitted by using a first frequency band of the
plurality of frequency band, and receives from the other radio communication
apparatus a first channel state information request; and
a transmission unit which transmits to the another radio communication
apparatus an information relating to a channel state for a frequency band
specified by the carrier indicator and corresponded with the first frequency
band, when the reception unit receives the first channel state information
request requesting the information relating to the channel state.
44. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a transmission unit which transmits to the another radio communication
apparatus a control information for a first data block of control information for
MIMO communication as a first channel state information request

corresponding to each of the plurality of frequency band, and transmits to the
another radio communication apparatus a second channel state information
request requesting an information relating to a channel state; and
a reception unit which receives from the another radio communication
apparatus the information relating to the channel state for the frequency band
specified by the first channel state information request.
45. A radio communication apparatus for performing radio communication by
using a plurality of frequency bands with another radio communication
apparatus, the apparatus comprising:
a reception unit which receives from the another radio communication
apparatus a control information for a first data block of control information for
MIMO communication as a first channel state information request
corresponding to each of the plurality of frequency band, and receives from the
other radio communication apparatus a second channel state information
request; and
a transmission unit which transmits to the another radio communication
apparatus an information relating to a channel state for the frequency band
specified by the first channel state information request, when the reception unit
receives the second channel state information request requesting the
information relating to the channel state.
46. The radio communication method according to any one of Claims 1, 7,
11,16,18, 20, 23, 24 and 26, wherein the second radio communication
apparatus transmits the information relating to the channel state to the first
radio communication apparatus with a timing delayed from a threshold value.
47. The radio communication apparatus according to any one of Claims 28,
30, 32, 34, 36, 38, 40, 42 and 44, wherein the reception unit receives the
information relating to the channel state from the another radio communication
apparatus with a timing delayed from a threshold value.

48. The radio communication apparatus according to any one of Claims 29,
31, 33, 35, 37, 39, 41, 43 and 45, wherein the transmission unit transmits the
information relating to the channel state to the another radio communication
apparatus with a timing delayed from a threshold value.