RADIO BASE STATION, RELAY STATION, AND BAND ALLOCATION
METHOD
FIELD
The present invention relates to a radio base
station, relay station, and band allocation method using
radio communication, and more particularly to a radio base
station and the like for appropriately allocating a band
between a radio terminal and a radio base station via a
relay station.
BACKGROUND
In IEEE 802.16WG, which is known as an example of a
radio communication system standard, two types of radio
communication systems are specified: IEEE 802.16d concerns
fixed communication (e.g. see the following Non-patent
Document 1), and IEEE 802.16e concerns mobile communication
(e.g. see the following Non-patent Document 2).
FIG. 20 depicts an image of the services provided by
IEEE 802.16d and IEEE 802.16e. These services are based on
a P-MP (Point-to-Multipoint) connection, where a plurality
of terminals 101 to 103 are connected to one radio base
station 100.
In this way, IEEE 802.16d or the like is based on a
P-MP connection, so the service area is limited to a cover
area (cell) covered by the radio base station 100, and the
communication rate drops at the cell edge.
To solve this problem, in IEEE 802.16WG, a relay
station to relay communication between a radio base station
and radio terminals is under consideration (IEEE 802.16j).
On the other hand, in IEEE 802.16d and IEEE 802.16e,
radio communication is performed between a radio base
station and a radio terminal after a bandwidth, sufficient
for radio communication (values specified by sub-channel and
symbol), is allocated. FIG. 21 is a diagram depicting an
example of the band allocation sequence performed between a
radio terminal MS and a radio base station BS.
First, the radio terminal MS sends a CDMA code

included in a code group for a Bandwith-Request (hereafter
called "BW Req Code") which indicates a band request out of
a CDMA code (signal sequence) group (S200).
Other than use for the Bandwith-Request, CDMA codes
are used for the adjustment of transmission parameters, such
as power, frequency and timing to communicate with the radio
base station BS, for Initial-Ranging for MS' network entry,
for Periodic-Ranging for correcting transmission parameters
periodically, and for Handover-Ranging which is used for
switching the radio base station BS.
Then the radio base station BS sends a UL-MAP
message (S201). FIG. 22 depicts an example of the format of
a UL-MAP message. In this UL-MAP message, a CDMA Allocation
IE is added as an information element. The radio base
station BS, which received the BW Req code sucessfully,
inserts information to allocate a band sufficient for
sending a band request message from the radio terminal MS
(Duration) into this CDMA Allocation IE field, in addition
to the information on receive Code (e.g. Value of Code,
timing when Code is transmitted, and information on the sub-
channel) .
As FIG. 22 depicts, "Frame Number Index" in the CDMA
Allocation IE indicates a frame number when the CDMA code is
sent, "Ranging Code" indicates the index of the CDMA code,
and "Ranging Symbol" and "Ranging Sub-channel" indicate a
symbol and sub-channel when the CDMA Code was sent
respectively. By this information, the transmitter of CDMA
code can identify whether the CDMA Allocation IE is
addressed to itself, and can transmit the band request
message using the band specified by "Duration".
In FIG. 22, two UIUC fields exist in the UL-MAP:
where the first UIUC indicates the CDMA Allocation IE, and
the second UIUC is an identifier which indicates a
modulation method and encoding method used by the radio
terminal MS in the allocated band. Normally the radio base
station BS has not specified the radio terminal MS in this
stage, so the modulation method (e.g. QPSK) and encoding
method, with which communication is possible with any radio

terminal MS, is specified.
Returning to FIG. 21, the radio terminal MS, which received the UL-MAP message
including the CDMA Allocation IE, sends a band request message ("BW Req GMH" in
FIG. 21) for requesting a band sufficient for transmitting a data packet to the radio
base station BS using the band allocated by the UL-MAP message (S202).
FIG. 23A depicts a format example of the band request message Ml, and FIG.
23B describes the values inserted in each field. The requested band is inserted in the
BR (Bandwidth Request) field.
Returning to FIG. 21, the radio base station BS, which received the band request
message, judges whether allocation is possible, and allocates a predetermined band to
the radio terminal MS using the UL-MAP message (S203).
The UL-MAP message includes the CID (Connection Identifier) to indicate an identifier
of the connection, UIUC which indicates the modulation method and encoding method,
and Duration which indicates the band amount to be allocated.
Then the radio terminal MS sends the data packet using the allocated band
(S204).
Non-patent Document 1: IEEE Std 802.16-2004
Non-patent Document 2: IEEE Std 802.16e-2005
JP 2006-157890 discloses To decrease the interference under a communication
environment where a plurality of radio communication modes exist mixedly, and to
enhance the communication quality. ; SOLUTION: A radio part 210 receives
communication profile information to output it to a communication permission
generator 220. The communication profile information contains at least information on
use radio communication mode, use frequency bandwidth, communication start time
and communication continuing time out of a radio resource shared by the plurality of
radio communication modes in the radio communication system. Further, the radio part
210 transmits communication permission/non-permission information. The
communication permission generator 220 refers to the communication profile
information and communication permission history stored in a storage part 230, and

produces the communication permission/non-permission information for
communications of the communication profile information.; The storage part 230 stores
the communication permission/non-permission information as the communication
permission history. ; COPYRIGHT: (C)2006,JPO&NCIPI
JP 2005-341604 says to transmit a large amount of user information from a base
station to a terminal at high speed by making the transmission rate of radio signals
wireless to a downlink line high in relative to an uplink line, to sufficiently deal with
requests of users and to effectively utilize frequencies. ; SOLUTION: In a radio
communication method, relating to a basic configuration, for performing radio
communication between a radio terminal and one or more radio base stations, a first
radio transmission band which uses a radio wave of a first frequency band, is used to
perform first radio communication between a terminal transmission means provided in
the radio terminal and any one or more base station receiving means of the base
stations, and a second radio transmission band at higher speed than the first radio
transmission band using radio waves of a second frequency band higher than the first
frequency band is used to perform second radio communication between the base
station transmission means of any one or more radio base stations and a terminal
receiving means of the radio terminal. ; COPYRIGHT: (C)2006,JPO&NCIPI
DISCLOSURE OF THE INVENTION
The above mentioned band allocation is directly performed between the radio
terminal MS and the radio base station BS, and does not disclose how the band is
allocated when a relay station intervenes.
Accordingly, it is an object in one aspect of the present invention is to provide a
radio base station, relay station, and band allocation method which can appropriately
allocate a band in a radio communication between a radio terminal and the radio base
station via the relay station.
Another aspect of the present invention is to provide a radio base station or the
like which can allocate a band at high-speed without delay.

According to one aspect of the present invention, a
relay station for relaying communication between a radio
base station, which allocates to a terminal an uplink
channel for notifying a requested band when any signal
sequence out of a predetermined signal sequence group is
received from the terminal, and allocates a transmission
band according to the requested band notified from the
terminal via the channel, and the terminal, including a
transmission unit which sends a specific signal sequence not
included in the predetermined signal sequence group, wherein
the relay station is allocated a predetermined transmission
band by the radio base station, without the relay station is
not allocated the uplink channel for notifying the requested
band by the radio base station which has received the
specific signal sequence.
According to another aspect of the present invention,
a radio base station for allocating to a terminal an uplink
channel for notifying a requested band when any signal
sequence out of a predetermined signal sequence group is
received from a terminal, and allocates a transmission band
according to the requested band notified from the terminal
via the channel, including: a control unit which allocates a
predetermined transmission band to a relay station, without
allocates the uplink channel for notifying the request band,
when a specific signal sequence not included in the
predetermined signal sequence group is received from the
relay station.
According to another aspect of the present invention,
a band allocation method in a radio base station in a radio
communication system which performs radio communication
between the radio base station and a terminal via a relay
station, the band allocation method including: allocating to
the terminal a transmission band for transmitting data to
the relay station; and allocating to the relay station a
band for transmitting the data to the radio base station,
without receiving allocation request of an other band from
the relay station after allocating the transmission band.
According to the present invention, a radio base

station, relay station, and band allocation method, which
can appropriately allocate a band in a radio communication
between a radio terminal and the radio base station via the
relay station, is provided. Also according to the present
invention, a radio base station or the like which can
allocate a band at high-speed without delay can be provided.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram depicting a sequence example
according to a first embodiment;
FIG. 2 is a diagram depicting a sequence example
according to the first embodiment;
FIG. 3 is a diagram depicting a sequence example
according to a second embodiment;
FIG. 4A depicts an example of a management table,
and FIG. 4B is a flow chart depicting an example of
processing in the radio base station;
FIG. 5 is a flow chart depicting an example of
processing in the radio base station;
FIG. 6 is a block diagram depicting a configuration
example of the radio base station;
FIG. 7A to FIG. 7C depict examples of the management
table;
FIG. 8 is a block diagram depicting a configuration
example of a relay station;
FIG. 9 is a flow chart depicting an example of
processing in the relay station;
FIG. 10A and FIG. 10B depicts examples of the
management table;
FIG. 11A is a flow chart depicting an example of
processing in the radio base station, and FIG. 11B depicts
an example of the management table;
FIG. 12A depicts an example of an association table,
and FIG. 12B is a diagram depicting a sequence example
according to a fifth embodiment;
FIG. 13A is a diagram depicting a sequence example
according to a sixth embodiment, and FIG. 13B is a diagram
depicting a format example of a second band request message;

FIG. 14 is a block diagram depicting a configuration
example of a relay station;
FIG. 15A is a flow chart depicting an example of
processing in the radio base station, and FIG. 15B is a flow
chart depicting an example of processing in the relay
station;
FIG. 16A is a diagram depicting a sequence example
according to a seventh embodiment, and FIG. 16B is a flow
chart depicting an example of processing in the radio base
station;
FIG. 17A is a diagram depicting a sequence example
according to an eighth embodiment, and FIG. 17B and FIG. 17C
depict examples of a field including delay information;
FIG. 18 depicts a format example of an SBC-REQ
message;
FIG. 19A is a diagram depicting a sequence example
according to a ninth embodiment, and FIG. 19B depicts an
example of information included in RNG-REQ;
FIG. 20 is a diagram depicting an image of a service
according to a prior art;
FIG. 21 is a diagram depicting a sequence example
according to a prior art;
FIG. 22 depicts a format example of a UL-MAP
message; and
FIG. 23A depicts a format example of a band request
message, and FIG. 23B depicts description thereof.
BEST MODE FOR CARRYING OUT THE INVENTION
Preferred embodiments of the present invention will
now be described.
First embodiment
FIG. 1 and FIG. 2 are diagrams depicting sequence
examples of band allocation according to a first embodiment.
FIG. 1 is an example when a radio base station BS generates
a UL-MAP message to allocate a transmission band to a radio
terminal MS under a relay station RS (Centralized
Scheduling), and FIG. 2 is an example when the relay station
RS generates a UL-MAP message (Distributed scheduling). A

radio communication system has the radio terminal MS, relay
station RS and radio base station BS.
FIG. 1 will be described first. The radio terminal
MS sends one CDMA code, included in a BW Req Code (signal
sequence) group which indicates a band request, out of a
CDMA code (signal sequence) group, to the relay station RS
(S10). The BW Req Code group may be created by one CDMA
code.
The relay station RS which received this CDMA code
notifies such information (BW Req Msg) as the value of the
code received from the radio terminal MS, transmission
timing thereof, and sub-channel to the radio base station,
but for this, the transmission band must be secured first.
Therefore, the relay station RS selects one CDMA
code included in the BW Req Code group, and sends it to the
radio base station BS, just like the radio terminal MS (Sll).
The radio base station BS which received this BW Req
Code cannot specify the relay station RS which sent this
code. Hence the radio base station BS sends the UL-MAP
message including a CDMA Allocation IE to the relay station
RS so that a channel in the uplink direction, sufficient for
the relay station RS to send a band request message, is
allocated (S12). The CDMA Allocation ID contains an
information including the value of this code, transmission
timing, sub channel and Frame Number Index. Then the relay
station RS sends a band request message (BW Req GMH) to the
radio base station BS using the allocated channel in the
uplink direction (S13).
The band request message is for requesting a
transmission band required for transmitting a message (BW
Req Msg in Fig.l) including the information on the code
which the relay station RS received. The radio base station
BS sends the CDMA Allocation IE to the radio terminal MS
based on the BW Req Msg later (S16).
Then the radio base station BS judges whether band
allocation is possible, and allocates a predetermined band
to the relay station RS using the UL-MAP message, when it is
possible (S14).

The relay station RS sends the transmission
information message (BW Req Msg), which is used for band
allocation from the radio base station BS to the radio
terminal MS, to the radio base station BS, using the
allocated predetermined band (S15).
The transmission information message includes an
individual information on received codes, such as Frame
Number Index, Ranging Code, Ranging Symbol, and Ranging Sub-
channel .
Then the radio base station BS sends the UL-MAP
message, including the CDMA Allocation IE, to the radio
terminal MS (S16).
Then the radio terminal MS sends a band request
message (BW Req GMH) to request a band to transmit the data
packet to the relay station RS (S17).
The relay station RS sends the BW Req Code again to
the radio base station BS, in order to receive band
allocation to send the band request message to the radio
base station BS (S18).
The radio base station BS allocates the band (S19),
and the relay station RS sends the band request message
received from the radio terminal MS using the allocated band
(S20).
The radio base station BS judges whether band
allocation is possible, and allocates the band to send the
data packet to the radio terminal MS using UL-MAP when it is
possible (S21).
The radio terminal MS sends the data packet to the
relay station RS (S22).
Then in order to receive the band allocation for
sending the data packet to the radio base station BS, the
relay station RS sends the BW Req Code to the radio base
station BS (S23). The radio base station BS allocates a
band to send the band request message (BW Req GMH) to the
relay station RS (S24), and using this band, the relay
station RS sends the band request message to receive the
band allocation for sending the data packet (S25). The
radio base station BS allocates the band for sending the

data packet to the relay station RS (S26), and the relay
station RS sends the data packet to the radio base station
BS using this band (S27).
Now FIG. 2 will be described where the relay station
RS generates a UL-MAP message for allocating a band to the
radio terminal MS.
First the radio terminal MS sends BW Req Code to the
relay station RS (S30). Just like the example in FIG. 1,
for the relay station RS to send the CDMA Allocation IE to
the radio terminal MS, the radio terminal MS must be
notified of such information as a value of the code, and the
transmission timing and sub-channel thereof, and therefore
sends this BW Req Code so as to receive allocation of a band
sufficient for sending this information.
Then the relay station RS sends the CDMA Allocation
IE with the allocated band for sending the band request
message, to the radio terminal MS (S31).
The radio terminal MS sends a band request message
(BW Req GMH) to receive allocation of a band to send a data
packet, using the allocated band (S32).
The relay station RS allocates a band to the radio
terminal MS using the UL-MAP message, based on the band
request message (S33).
The radio terminal MS sends the data packet to the
relay station RS, using the allocated band (S34).
The relay station RS requests the radio base station
BS to allocate a band to send the received data packet,
using BW Req Code (S35).
The radio base station BS sends the CDMA Allocation
IE with the allocated band for sending the band request
message to the relay station RS (S36), and using the band,
the relay station RS sends a band request message for
receiving allocation of a band to send a data packet to the
base station BS (S37) .
The base station BS allocates a band using the UL-
MAP message (S38), and the relay station RS sends the data
packet to the radio base station BS using the allocated band
(S39).

As described above, according to the above examples,
the data packet can be sent from the radio terminal MS to
the radio base station BS via the relay station RS using an
allocated band by sequentially sending code, message or the
like via the relay station RS, so band allocation can be
performed appropriately.
Second embodiment
Now a second embodiment will be described with
reference to FIG. 3 to FIG. 9.
The second embodiment is an example when the speed
of the processing is higher than the speed of the processing
of the first embodiment. In the second embodiment, the
relay station RS, which received one CDMA code included in a
predetermined CDMA code (signal sequence) group for BW Req
(e.g. Codes 1, 2, 3) from the radio terminal MS, sends a
predetermined specific CDMA code for BW Req (e.g. Code 4) to
the radio base station BS.
In other words, the relay station uses a code, which
is different from the CDMA code which the radio terminal MS
uses for BW Req, as a specific code for the BW Req.
The radio base station BS which received this
specific code recognizes that the band request is not from
the radio terminal MS, but from the specific relay station
RS, and allocates a required transmission band
(predetermined band) to the relay station RS without having
the relay station RS send the band request message.
If a plurality of relay stations exist under the
radio base station BS, it is preferable to allocate a
specific code to each relay station in advance, so that each
relay station uses the allocated code as the specific code.
This is because the relay station can be specified depending
on the type of code, even if a plurality of relay stations
exists.
After the band is allocated to the radio terminal MS,
it is expected that the relay station RS will transfer the
transmission data from the radio terminal MS to the radio
base station BS, so a band required for transmitting a next
message (see S47 in FIG. 3) is automatically allocated from

the radio base station BS to the relay station (S46) so as
to omit the band allocation request from the relay station
RS, whereby a processing delay can be suppressed.
The radio communication system has the radio
terminal MS, relay station RS and radio base station BS,
just like the first embodiment. This is the same for the
third and later embodiments. FIG. 3 is a diagram depicting
an example of the band allocation sequence according to the
second embodiment.
First in order to receive allocation of a band from
the radio base station BS, the radio terminal MS sends one
code included in the BW Req code group for the radio
terminal to the relay station RS (S40), just like the first
embodiment.
The relay station RS sends the specific BW Req code
to the radio base station BS (S41). This code is a specific
code allocated to the relay station RS in advance (a code
which can be distinguished from the code used by the radio
terminal). The radio base station BS which received this
specific code can specify the relay station RS which sent
this code.
FIG. 3 depicts an example when the radio terminal MS
sends BW Req Code, but may send a different code, such as a
code for Ranging, in the same way (details will be described
in the ninth embodiment).
Therefore according to the second embodiment, some
of a plurality of CDMA codes (e.g. 225 codes) are allocated
not only to the four applications described above but also
to the relay station RS, so as to obtain the predetermined
band. (This is the same for the third and later embodiments
to be described below.)
Allocation of the specific BW Req Code to the relay
station RS can be performed when the relay station RS is
performed by when the relay station RS is connected to the
radio base station BS for example. This allocation may be
included in such a message as a ranging response message
(RNG-RSP ((Ranging Response)), basic function response
message (SBC-RSP (SS Basic Capability Response)), and

registration response message (REG-RSP (Registration
Response)), which is sent from the radio base station BS to
the relay station RS, for example.
Then the radio base station BS specifies the
transmission source relay station RS using the received
specific code, and allocates a predetermined band for
sending the transmission information message (BW Req Msg) to
the relay station RS using the UL-MAP message (S42). In
other words, the radio base station BS automatically
allocates a predetermined band for sending the transmission
information message to the relay station RS, when the radio
base station BS receives the specific code.
The transmission information message includes
information required for the radio base station BS to send
the CDMA Allocation IE to the radio terminal MS (e.g. Frame
Number Index, Ranging Code, Ranging Symbol, Ranging Sub-
channel) , just like the first embodiment
Also, the UL-MAP message includes Duration to
indicate a band to be allocated, CID (Connection Identifier)
for identifying a connection, and UUIC to indicate the
encoding method and modulation method, just like the first
embodiment. Since the allocation destination relay station
RS is specified, CID can also be specified, and the optimum
encoding and modulation method for the relay station RS can
also be specified using UUIC.
In order to search the transmission source relay
station RS when the radio base station BS received the
specific code, a first management table Tl depicted in FIG.
4A is stored in the radio base station BS. This is a table
to indicate the relay station RS corresponding to each
specific code. It is assumed that each relay station RS and
radio base station BS share information in advance based on
RNG-RSP or the like, so as to specify each specific code and
each relay station RS.
Returning to FIG. 3, the relay station RS then sends
the transmission information message using the allocated
band (S43). Each information included in the transmission
information message is readied for transmission to the radio

station BS since the relay station RS stores the reception
result when the code is received from the radio terminal MS.
Then the radio base station BS generates the UL-MAP
message including the CDMA Allocation IE based on the
transmission information message, and sends it to the radio
terminal MS (S44).
Using the band allocated by the CDMA Allocation IE,
the radio terminal MS sends the band request message (BW Req
GMH) to the relay station RS (S45).
Here the relay station RS requires a band for
sending this band request message to the radio base station
BS, to be allocated by the radio base station BS, but in
this case BW Req Code is not sent to the radio base station
BS. This is because the radio base station BS automatically
allocates the band for sending the band request message (BW
Req GMH) to the relay station RS when a predetermined time
has elapsed from reception of BW Req GMH (S46), after
sending the CDMA Allocation IE (S44). It is preferable that
this predetermined time is notified from the relay station
RS to the radio base station BS by one of RNG-REQ, SBC-REQ
and REG-REQ, which is sent when the relay station RS starts
connection to the radio base station BS (Details will be
described later in the eighth embodiment). This
predetermined time can be a processing time which the relay
station requires to send BW Req GMH.
The relay station RS sends the band request message
(BW Req GMH) from the radio terminal MS to the radio base
station BS, using the allocated band (S47).
The radio base station BS judges whether the band
allocation is possible and allocates a band to the radio
terminal MS using the UL-MAP message, based on the received
band request message (S48).
The radio terminal MS sends the data packet to the
relay station RS using the allocated band (S49).
The relay station RS does not send BW Req Code to
indicate the band request to send the data packet to the
radio base station BS, as mentioned above. The radio base
station BS allocates the band sufficient to send the data

packet using the UL-MAP message (S48), then allocates the
band sufficient to send a data volume that the radio
terminal MS can send, to the relay station RS after a
predetermined time has elapsed, considering a processing
delay in the relay station RS (S50). This processing delay
is also notified to the radio base station BS using RNG-REQ
or the like when connection is started.
The relay station RS sends the data packet from the
radio terminal MS to the radio base station BS, using the
allocated band (S51).
In this way, according to the second embodiment, the
relay station RS, which received the BW Req Code from the
radio terminal MS, sends a specific BW Req Code to the radio
base station BS, and when this code is received, the radio
base station BS allocates the predetermined band sufficient
to send the transmission information message to the relay
station RS. Therefore the predetermined band is allocated
to the relay station RS by the radio base station BS even if
the relay station RS does not request the band to the radio
base station BS, so the required band allocation can be
performed at high-speed. In concrete terms, the second
embodiment can perform band allocation faster than the first
embodiment, since the processings in S12 and S13 in the
first embodiment are not performed.
When the relay station RS sends the band request
message from the radio terminal MS to the radio base station
BS as well, the relay station RS does not request the band
to the radio base station BS, instead the radio base station
BS allocates the band sufficient to send the band request
message to the radio terminal MS, and after the
predetermined time has elapsed, the radio base station BS
allocates the band, which is sufficient for the relay
station RS to send the band request message to the radio
base station BS, to the relay station RS. Therefore the
relay station RS need not send the BW Req Code to the radio
base station BS, and the speed of processing can be
increased.
For the transmission of the data packet from the

radio terminal MS as well, the radio base station BS
allocates a band, then after the predetermined time has
elapsed, the radio base station BS allocates the band
sufficient to send the data packet, to the relay station RS,
considering the processing delay, so the speed of band
allocation can be increased without sending a band request.
FIG. 4B is a flow chart depicting a processing when
the radio base station BS received BW Req Code, and FIG. 5
is a flow chart depicting a processing when the radio base
station BS allocates a band.
As FIG. 4B depicts, when BW Req Code is received
(S60), the radio base station BS judges whether this code is
specific code of the relay station RS (specific BW Req Code)
(S61). If it is a specific code (Y), the radio base station
BS generates the UL-MAP message to which CID, Duration and
UUIC corresponding to the code are attached, and sends this
UL-MAP message to the relay station RS (S62). This is a
processing corresponding to S42 in FIG. 3.
On the other hand, if not the specific code (N in
S61), the radio base station BS generates the UL-MAP message
to which the CDMA Allocation IE is attached, and sends this
UL-MAP message to the relay station RS. This is a
processing corresponding to S12 in FIG. 1. The processing
is repeated hereafter.
For the processing after band allocation, as
depicted in FIG. 5, the radio base station BS judges whether
the band is allocated to the radio terminal MS (S70), and
the processing for band allocation is repeated (loop of N).
This is a processing corresponding to S44 and S48 in FIG. 3.
If the band allocation is performed (Y in S70), the
radio base station BS judges whether the radio terminal MS,
to which the band is allocated, is communicating via the
relay station RS (S71). For example, the radio band station
BS has a management table to indicate a communication path
of each radio terminal MS, and refers to this table for this
j udgment.
If not via the relay station RS (N), the radio base
station BS moves back to S70, and repeats processing. If

via the relay station RS (Y in S71), the radio base station
BS allocates the band to the relay station RS after the
predetermined time has elapsed (S72). This is a processing
corresponding to S46 and S50 in FIG. 3. This processing is
repeated hereafter.
Now a configuration example of the radio base
station will be described. FIG. 6 is a block diagram
depicting a configuration example of the radio base station
BS. The radio base station BS has a receive unit 11,
control message extraction unit 12, packet regeneration unit
13, NW interface unit 14, code receive unit 15, MAP
information generation unit 16, control message analysis
unit 17, packet identification unit 18, packet buffer unit
19, PDU generation unit 20, and transmission unit 21.
When a code is received from an antenna 22, the
receive unit 11 outputs information on the code to the code
receive unit 15. When the message or data packet, other
than code, is received, the receive unit 11 outputs it to
the control message extraction unit 12.
The control message extraction unit 12 extracts a
control message such as the band request message (BW Req
GMH), and outputs it to the control message analysis unit 17.
Other user packets are output to the packet regeneration
unit 13 and are sent to a host network via the NW interface
unit 14.
The code receive unit 15 outputs information on the
received code and allocation band amount corresponding to
the code value (amount for the band request message (amount
for BW Req GMH) if BW Req Code is used) to the MAP
information generation unit 16.
If the received code value is the specific code
(specific BW Req Code), the code receive unit 15 notifies
the MAP information generation unit 16 to generate the UL-
MAP to allocate the predetermined band to the relay station
RS. The band allocation is performed considering the
modulation method and encoding method to be used for the
communication with the relay station RS.
On the other hand, in the case of other codes, the

transmission source of the code cannot be specified, so the
code receive unit 15 requests the MAP information generation
unit 16 to allocate the band using the CDMA Allocation IE.
The control message analysis unit 17 analyzes the
band request message and specifies a transmission node (e.g.
relay station RS) based on the CID of this message, and
requests the MAP information generation unit 16 to allocate
the required band, considering the modulation method and
encoding method being used for the communication with the
transmission node.
The MAP information generation unit 16 generates the
MAP information based on the information from the code
receive unit 15 or control message analysis unit 17. For
the packet in the downlink direction received by the packet
identification unit 18 via the NW interface unit 14, the
packet identification unit 18 judges the destination radio
terminal MS and QoS (Quality of Service) class, and notifies
this information to the MAP information generation unit 16.
Based on this information, the MAP information generation
unit 16 generates and sends the MAL information in the
downlink direction (DL-MAP).
When the predetermined time has elapsed after
allocating the band to the radio terminal MS, the MAP
information generation unit 16 allocates the band to the
relay station RS which relays communication with the radio
terminal MS. In this case, the modulation and encoding
method (including the encoding rate) when the radio terminal
MS communicates with the relay station RS may be different
from when the relay station RS communicates with the radio
base station BS, so the band sufficient to transmit the same
data volume in these two communications is allocated.
For example, if the modulation method of the radio
terminal MS is QPSK and the encoding rate thereof is 1/2,
and if the modulation method of the relay station RS is
16QAM and the encoding rate thereof is 1/2, then the
bandwidth of the band to be allocated to the relay station
RS can be half of the band to be allocated to the radio
terminal MS.

In the case of downlink as well, when the
predetermined time has elapsed, after the data address to
the radio terminal MS is sent to the relay station RS, the
MAP information generation unit 16 allocates the band for
the relay station RS to send this data to the radio terminal
MS, even if the band request is not received from the relay
station RS. The allocation is notified to each node (relay
station RS and radio terminal MS) using DL-MAP. Downlink
will be described in the seventh embodiment.
FIG. 7A to FIG. 7C depicts examples of the
management tables to perform these processings. The MAP
information generation unit 16 specifies the relay station
RS to relay communication with the radio terminal MS using
the second management table T2 (FIG. 7A), specifies the
processing delay using the third management table T3 (FIG.
7B), and specifies the modulation method and encoding method
of the communication target radio terminal MS and relay
station RS using the fourth management table T4 (FIG. 7C).
The processing delay of each relay station RS may be a
number of frames, instead of the time depicted in FIG. 7B.
Now the configuration and operation of the relay
station RS will be described. FIG. 8 is a block diagram
depicting a configuration example of the relay station RS.
The relay station RS has a receive unit 31, control message
extraction unit 32, PDU buffer unit 33, transmission unit 34,
code receive unit 35, control message generation unit 36,
MAP information analysis unit 37, and code generation unit
38.
When the code (BW Req Code) sent from the radio
terminal MS is received, the receive unit 31 outputs
information on the code (information to transmit CDMA
Allocation IE, such as code value, sub-channel which
received the code, and symbol timing) to the code receive
unit 35. The receive unit 31 also outputs information other
than code (control messages and data packets) sent from the
radio terminal MS and radio base station BS to the control
message extraction unit 32.
The control message extraction unit 32 extracts the

MAP information (UL-MAP, DL-MAP) from the control message,
and outputs it to the MAP information analysis unit 37, and
outputs the user packet to the PDU buffer unit 33.
The user packet is sent from the PDU buffer unit 33
to the radio terminal MS or radio base station BS via the
transmission unit 34 and antenna 39.
The code receive unit 35 requests the control
message generation unit 36 to generate a message to notify
the information on the code to the radio base station BS
(e.g. transmission information message (message transmitted
in S43)). The code receive unit 35 also requests the MAP
information analysis unit 37 to send the code to receive the
band allocation to send the message (e.g. specific code
transmitted in S41 in FIG. 3).
The control message generation unit 36 generates a
message to be sent to the radio station BS, based on the
information on the code sent from the code receive unit 35,
and outputs it to the PDU buffer unit 33 which stores this
message.
The MAP information analysis unit 37 analyzes the
UL-MAP message from the control message extraction unit 32
(e.g. UL-MAP message received in S42 in FIG. 3), and
acquires Sub-channel and Symbol timing with which code
transmission is allowed, then the MAP information analysis
unit 37 instructs the code generation unit 38 to generate
the code (specific code) based on the code transmission
notice received from the code receive unit 35, so that the
acquired code is sent from the transmission unit 34 at the
acquired code transmission timing of the code.
For the message which is stored from the control
message generation unit 36 to the PDU buffer unit 33 (e.g.
transmission information message), transmission of the
message from the PDU buffer 33 is controlled based on the
band allocation analyzed by the MAP information analysis
unit 37.
The code and message are sent to the radio base
station BS and radio terminal MS from the transmission unit
34 via the antenna 39.

FIG. 9 is a flow chart depicting an example of
processing executed in the relay station RS when the code is
received from the radio base station BS.
When the code (BW Req Code in S10 in FIG. 3) is
received from the radio terminal MS (Y in S80), the relay
station RS generates the message to send the Code value,
Frame Index, Sub-channel and Symbol to the radio base
station BS (transmission information message) (S81).
The relay station RS judges whether the band to send
the generated message is available (S82). The relay station
RS judges this depending on whether the band sufficient to
send this message was received.
If the band to send the message is available (Y),
the relay station RS sends the message generated in S81 to
the radio base station BS (S84). This processing
corresponds to S43 in FIG. 3.
If the band to send the message is not available (N
in S82), the relay station RS sends the specific BW Req Code
to the radio base station BS (S83). This processing
corresponds to S41 in FIG. 4.
Third embodiment
Now a third embodiment will be described.
In the second embodiment, the example of the relay
station RS sending BW Req Code indicated by the specific
code, out of the CDMA codes to request the band, is
described. The BW Req Code indicated by the specific code
is allocated to each relay station RS independently (see FIG.
4A) .
In the third embodiment, an identical specific code
is allocated to a plurality of relay stations RS. A common
CID (Connection ID, called a Multicast Polling CID in the
third embodiment) is allocated to the relay station RS where
identical specific code is allocated.
For example in FIG. 3, the relay station RS sends
the BW Req Code indicated by the specific code (S41) , but
here the specific code commonly allocated to each relay
station RS is sent. The radio base station BS which
received this code recognizes that this is the band request

from the relay station RS, and generates the UL-MAP message
which includes information to allocate the band in the
Multicast Polling CID, and sends it (S42). The specific
code commonly allocated is generated by the code generation
unit 38 of the relay station RS, and the UL-MAP message,
including the Multicast Polling CID, is generated by the MAP
information generation unit 16 of the radio base station BS.
FIG. 10A is an example of a fifth management table
T5, which depicts the correspondence of CDMA code and
Multicast Polling CIDs. The radio base station BS refers to
the fifth management table T5 and creates the UL-MAP message.
The radio base station BS inserts a corresponding Multicast
Polling CID to the "CID" field of the UL-MAP message (see
FIG. 22), and sends the UL-MAP message.
In the first and second embodiments, the CID of each
relay station RS, which is the CID to indicate each relay
station RS, is inserted in the "CID" field. In the third
embodiment, the common CID of the relay station RS is
inserted in the "CID" field. By allocating an identical CID
to a plurality of relay stations RS like this, the resources
of specific codes can be saved. The subsequent processing
is the same as the second embodiment.
A same band is allocated to each relay station RS to
which the common CID is allocated, and each relay station RS
can send the band request message to the radio base station
BS using this band. For the allocation of the individual
CID according to the second embodiment as well, a different
band is allocated to each relay station RS.
It is preferable to allocate the identical CID for
the Multicast Polling CID, to the radio base station BS to
communicate with based on an identical modulation method and
encoding method. Each relay station RS and the radio base
station BS are not always communicating based on the
identical modulation and encoding method, and if relay
stations RS and the radio base stations BS communicating
based on the same modulation and encoding method are grouped,
and the identical CID is allocated to the group, the
modulation and encoding method used for the allocated band

can be optimized.
FIG. 10B depicts a sixth management table T6
allocated like this. A common Multicast Polling CID
("0x0101") is allocated to a plurality of relay stations RS
("RS#1" and "RS#2") .
Fourth embodiment
Now a fourth embodiment will be described.
According to the second embodiment, if the band is
allocated to the radio terminal MS (S44, S48 in FIG. 3), the
band is automatically allocated to the relay station RS when
the predetermined time has elapsed (S46, S50 in FIG. 3).
Therefore if the relay station RS cannot normally
receive the data sent from the radio terminal MS, the band
allocated to the radio station RS may not be used and is
therefore wasted. In particular, the band allocation (S48
in FIG. 3) for the band request message (BW Req GMH, S45 and
S47 in FIG. 3) is for the data packet, and an error easily
occurs if the packet length is long. Also a wideband is
often allocated to the data packet, and if the relay station
RS cannot receive the data packet, the band allocation
becomes very inefficient.
To prevent this, it is judged which QoS (Quality of
Service) class of connection (CID) the band allocation to
the band request message is used for. The CID in the band
request message (see FIG. 23A and FIG. 23B) depicts a QoS
class (e.g. "best effort", "band securing") of data to be
sent next, so according to the class, a case of
automatically allocating the band and a case of allocating
the band based on a new band request message from the relay
station RS are separated. Thereby band allocation according
to the QoS class of data packet becomes possible.
FIG. 11A is a flow chart depicting a processing
operation in the radio base station BS when the band request
message is received from the relay station RS.
When the band request message (BW Req GMH) is
received (Y in S90), the radio base station BS judges
whether this is the high priority connection or not (S91).
FIG. 11B depicts an example of a seventh management table T7

for managing the correspondence of a connection and priority.
When the band request message is received from the relay
station RS, the radio base station BS extracts the CID from
the "CID" field in the message (see FIG. 23A and FIG. 23B),
and searches the priority in the seventh management table T7.
If priority is "high" as a result of the search, the
connection is "high priority connection", and if "low", the
connection is not "high priority connection".
This judgment is made by the control message
analysis unit 17 of the radio base station BS.
Returning to FIG. 11A, if "high priority connection"
(Y in S91), the radio base station BS allocates the band to
the radio terminal MS, then allocates the band to the relay
station RS when the predetermined time has elapsed (S92).
Then processing returns to S90, and the same processing is
repeated.
If not "high priority connection" (N in S91), the
radio base station BS waits for receiving the new band
request message from the relay station RS (S90), and the
processing is repeated.
According to the processing depicted in FIG. 11A,
band allocation from the radio base station BS is not
performed unless the CID of the band request message is high
priority connection. However, the band request can be
specified in the data packet, so if an insufficient band is
specified by this new band request, the connection can be
high priority connection, and the radio base station BS can
allocate the band to the relay station RS.
Since the rest of the processings are the same as
the second embodiment, the speed of band allocation
processing can be increased.
Fifth embodiment
Now the fifth embodiment will be described.
In the second embodiment, the specific code value
(value of a specific code in the second embodiment, see FIG.
4A) is allocated to the relay station RS, and the radio base
station BS specifies the relay station RS by requesting the
band using the code value, therefore the band can be

allocated to the relay station RS with specifying the
optimum modulation method or the like.
Generally the relay station RS is often arranged in
sight of the radio base station BS, and the communication
quality between them is good in many cases. In such the
case, the optimum modulation method or the like for each
relay station RS is more likely to be similar.
Therefore in such the case, instead of corresponding
the relay station RS to each code, each code can be directly
associated with the band to be requested, whereby
transmission of the band request massage (BW Req GMH) from
the relay station RS can be omitted, and the speed of band
allocation processing can be higher than the case of
processing.
FIG. 12A depicts an example of an association table
T8 which associates each code and band amount. The
association table T8 stores bands associated with each code
value to indicate a management band request.
FIG. 12B is a diagram depicting a sequence of
processing operation when the code and band are associated.
First the radio terminal MS sends BW Req Code to the
relay station RS (S100). The relay station RS allocates the
band sufficient to send the band request message using UL-
MAP (S101).
Using the allocated band, the radio terminal MS
sends the band request message (BW Req GMH) to the relay
station RS (S102), and the radio base station BS judges the
availability of the band requested by the band request
message, and allocates a predetermined band (S103).
The radio terminal MS sends the data packet to the
relay station RS, using the allocated band (S104).
The relay station RS sends BW Req Code to the radio
base station BS, using the code corresponding to the minimum
band required for sending the data packet (S105). For
example, if 15 bytes of transmission are required, code
0x1002 is sent.
The radio base station BS sends the UL-MAP message
including the CDMA Allocation IE to allocate the maximum

band corresponding to the received code, to the relay
station RS (S106). The modulation method and encoding
method to be used for the allocated band are those with
which all the relay stations RS can communicate with the
radio base station BS (inserted in the "UIUC" field).
Using the allocated band, the relay station RS sends
the data packet to the radio base station BS (S107).
By directly associating the code and band like this,
the band request message (BW Req GMH) from the relay station
RS to the radio base station BS, and the corresponding UL-
MAP message from the radio base station BS to the relay
station RS are omitted, and speed of the processing can be
faster than the speed of the first embodiment (FIG. 2).
In the processing of S105 in the relay station RS,
BW Req Code, using the code corresponding to the band
sufficient to send the data packet, is generated in the code
generation unit 38 based on the instruction of the MAP
information analysis unit 37, and is set. In the processing
of S106 in the radio base station BS, the code receive unit
15 determines the band amount according to the association
table T8, and outputs it to the MAP information generation
unit 16, and the MAP information generation unit 16
generates and sends the UL-MAP message.
Sixth embodiment
Now a sixth embodiment will be described. The sixth
embodiment is an example of a relay station RS generating a
UL-MAP message and allocating the band to the subordinate
radio terminal MS (Distributed Scheduling). In the sixth
embodiment, a desired band allocation time (Allocation Time)
is inserted in the band request message to be sent from the
relay station RS to the radio base station BS. When this
time arrives, the radio base station BS allocates the band
to the relay station RS, so the relay station RS can send
the data packet from the radio terminal MS to the radio base
station BS at an appropriate timing.
FIG. 13A is a diagram depicting an operation
sequence according to the present embodiment.
Firstly, the radio terminal MS sends BW Req Code to

the relay station RS (S110). The relay station RS sends BW
Req Code to the radio base station BS to request allocating
the band sufficient to send the band request message (Sill).
The relay station RS also sends the UL-MAP message
including the CDMA Allocation IE to the radio terminal MS,
so that the band request message from the radio terminal MS
can be sent (S112).
The radio terminal MS sends the band request message
(BW Req GMH) using the allocated band (S114). On the other
hand, the relay station RS receives the UL-MAP message
including the CDMA Allocation IE (S113), and sends the band
request message using this band (S115).
This band request message (hereafter called "second
band request message" in the sixth embodiment) includes a
desired allocation time. The desired allocation time is a
time when the relay station RS allocates the band to the
radio terminal MS (later mentioned S116), and receives a
time of receiving the data packet (S118) plus a processing
delay in the relay station RS, or a time just before the
time when the data packet is received from the radio
terminal MS and this data packet is sent to the radio base
station BS the quickest way.
FIG. 13B depicts a format example of the second band
request message. A desired time desired by the relay
station RS is inserted in the "Allocation Time" field. This
is a time elapsed from the time when the second band request
message is sent. The radio base station BS, which received
the second band request message, allocates the requested
band amount, or a part thereof, to the relay station RS
after at least the Allocation Time has elapsed.
Returning to FIG. 13A, the radio base station BS
allocates the band to the relay station RS when the desired
allocation time arrives (S117), and the relay station RS
receives the data packet from the radio terminal MS (S118),
and sends this data packet to the radio base station BS
using the allocated band (S119).
The block configuration example of the radio base
station BS of the sixth embodiment is the same as the second

embodiment (see FIG. 6). FIG. 14 is a block diagram
depicting a configuration example of the relay station RS.
The radio base station BS will now be described in
brief with reference to FIG. 6. The radio base station BS
operates roughly the same way as in the second embodiment,
but the difference is that if Allocation Time is included in
the band request message, the control message analysis unit
17 requests allocation of the band to the MAP information
generation unit 16 after the Allocation Time has elapsed.
And in the MAP information generation unit 16, the UL-MAP
message is generated and sent to the relay station RS.
Compared with the second embodiment (see FIG. 8), in
the configuration of the relay station RS of the sixth
embodiment, the relay station further has a control message
analysis unit 40 and MAP information generation unit 41,
instead of the MAP information analysis unit 37.
The MAP information generation unit 41 receives a
notice instructing that the band is allocated to the radio
terminal MS using the CDMA Allocation IE, along with the
received code value and allocation band amount, from the
code receive unit 35.
The control message analysis unit 4 0 analyzes the
UL-MAP received from the radio base station BS (from the
control message extraction unit 32), and acquires Sub-
channel and Symbol timing with which code can be sent, then
instructs the code generation unit 38 to generate and send a
predetermined code. The control message analysis unit 40
also instructs the PDU buffer unit 33 to send the data
packet and control message to be sent to the radio base
station BS, using the allocated band. If the band request
message is received from the radio terminal MS, the control
message analysis unit 40 notifies the content of the message
to the control message generation unit 36, and also notifies
the MAP information generation unit 41 to allocate the band
to the radio terminal MS.
The control message generation unit 36 generates the
second band request message including the band amount
requested by the radio terminal MS and time information,

stores it in the PDU buffer unit 33, and sends it to the
radio base station BS. The desired band allocation time is
a value of the time when this band is allocated to the radio
terminal MS, plus the processing delay of the relay station
RS, or later.
FIG. 15A is a flow chart depicting the operation of
processing of the radio base station BS according to the
present embodiment, and FIG. 15B is a flow chart depicting
the operation of the relay station RS.
As FIG. 15A depicts, when the band request message
is received from the relay station RS (Y in S120), the radio
base station BS judges whether Allocation Time is included
in the band request message (S121), and if included (Y), the
radio base station BS allocates the band to the relay
station RS after Allocation Time has elapsed (S122). On the
other hand, if Allocation Time is not included in the band
request message (N in S121), the radio base station BS
immediately allocates the band (S123).
If the relay station RS receives the band request
message from the radio terminal MS, as depicted in FIG. 15B
(Y in S130), the relay station RS judges whether the band
sufficient to send the band request message is available
(S131) .
If the band has already been secured (Y), the relay
station RS allocates the band to the radio terminal MS, and
sends the band request message to the radio base station BS
(S132). This corresponds to the processing from S114 to
S116 in FIG. 13A.
If the band is not available (N in S131), the relay
station RS sends CDMA code (BW Req Code) to indicate the
band request (S133). This corresponds to receiving the band
request message in S114, and sending the BW Req Code in S115
in FIG. 13A. The subsequent processing is the same as the
processing in S113 and later, although timing is shifted.
Seventh embodiment
Now the seventh embodiment will be described. The
seventh embodiment is an example of band allocation in the
downlink direction. FIG. 16A depicts the sequence diagram,

and FIG. 16B depicts the flow chart.
As FIG. 16A depicts, the radio base station BS
generates the DL-MAP message to allocate the band, to send
the data packet which is to be sent to the radio terminal MS
via the relay station RS, to the relay station RS, and sends
the DL-MAP message to the relay station RS (S140). This DL-
MAP message is generated by the MAP information generation
unit 16 (see FIG. 6).
The relay station RS receives the data packet from
the radio base station BS according to the received DL-MAP
message (S141). The data packet from the radio base station
BS is generated and sent by a path from the NW interface
unit 14 to the transmission unit 21 (see FIG. 6), for
example. In the relay station RS, the data packet is
received via the receive unit 31 (see FIG. 8).
The radio base station BS generates the DL-MAP
message to allocate the band for the relay station RS to
send the data packet to the radio terminal MS, and
broadcasts the DL-MAP message (S142, S143) .
This DL-MAP message is sent from the radio base
station BS to the radio terminal MS when the delay time,
considering the processing delay of the relay station RS,
has elapsed after the relay station RS received the data
packet from the radio base station BS, with specifying a
time when the relay station RS can send the data packet to
the radio terminal MS as the transmission timing. In other
words, for the transmission timing of the data packet
specified by the DL-MAP in S140, the transmission timing of
the data packet specified by the DL-MAP in S142 plus the
predetermined delay time is set.
The relay station RS sends the data packet to the
radio terminal MS, using the band allocated in the DL-MAP
received in S142, and the radio terminal MS receives the
data packet according to the information in DL-MAP (S144).
The band allocation operation in the radio base
station BS will be described with reference to FIG. 16B.
First the radio base station BS judges whether data
for downlink (DL Data) is received (S150), and waits until

this data is received if not received (loop N).
If this data is received (Y), the radio base station
BS judges whether this data is data addressed to the radio
terminal MS via the relay station RS (S151). As described
in the second embodiment, the radio base station BS stores
the management table to depict the transmission paths of the
radio terminal MS, and this judgment is made by referring to
this management table.
If the data is the data to the radio terminal MS via
the relay station RS (Y in S151), the radio base station BS
allocates the band to send this data, to the relay station
RS (S152). This is processing corresponding to S140 in FIG.
16A. This processing is performed by the MAP information
generation unit 16 (see FIG. 6).
The radio base station BS allocates the band for the
relay station RS to send data to the radio terminal MS
(S153). This is a processing corresponding to S142 in FIG.
16A, and is performed by the MAP information generation unit
16.
If the data is not data addressed to the radio
terminal MS via the relay station RS (N in S151), the radio
base station BS directly allocates the band for sending the
data to the radio terminal MS (S154). This is a processing
performed by the MAP information generation unit 16.
In this way, for the downlink direction as well, the
band can be appropriately allocated and the data packet can
be sent from the radio base station BS to the radio terminal
MS via the relay station RS. At this time, the band to send
the data packet from the radio station RS to the radio
terminal MS is allocated according to the timing at which
the transmission of the data packet from the relay station
RS becomes possible. Therefore the data packet can be sent
from the relay station RS to the radio terminal MS at an
appropriate timing.
The band allocation for the downlink direction
according to the seventh embodiment can also be performed
for the above mentioned third to sixth embodiments.
Eighth embodiment

Now the eighth embodiment will be described. In the
second embodiment, after the band is allocated to the radio
terminal MS, the band is automatically allocated to the
relay station RS after the predetermined time has elapsed.
The eighth embodiment is an example when the relay station
RS sends the predetermined time to the radio base station BS
in advance.
FIG. 17A is a diagram depicting an example of a
sequence according to the eighth embodiment. After power ON
(S160), the relay station RS executes ranging processing
(S161 to S164). This is a processing for adjusting the
timing and transmission power between the relay station RS
and radio base station BS.
Then a processing to notify a list of capabilities
related to the physical layers, such as maximum transmission
power, of the relay station RS to the radio base station BS
is performed (S165 to S166).
As FIG. 17B and FIG. 17C depict, time information
including delay information in the uplink direction or delay
information in the downlink direction is inserted in the TBA
field of an SBC-REQ (basic function) message, which is sent
from the relay station RS. FIG. 18 depicts an example of an
SBC-REQ message, in which the time information is inserted.
This message is generated by the control message unit 36 of
the relay station RS, for example.
Then processing to authenticate the relay station RS
and to exchange an encryption key used for encryption is
performed (S167 to S168), and processing to register the
capabilities of the MAC layer and upper layer is performed
(S169 to S170).
In this series of the initial sequence, the relay
station RS sends the SBC-REQ (basic function request
message), including the delay time, to the radio base
station BS in the example described above, but delay
information may be inserted in the ranging request message
(RNG-REQ), authentication request message (PKM-REQ) or
registration request message (REG-REQ). In this case, delay
information can be inserted in an open field or the like,

just like FIG. 18.
Thereby as depicted in the second embodiment, the
band is automatically allocated from the radio base station
BS to the relay station RS when the predetermined time (time
specified by the time information) has elapsed.
Ninth embodiment
Now a ninth embodiment will be described. In the
second embodiment, the band is allocated using CDMA code (BW
Req Code), which indicates the band allocation. The ninth
embodiment is an example of performing band allocation using
Ranging Code out of CDMA Code.
FIG. 19A is a diagram depicting a sequence example
of the ninth embodiment.
Firstly, the radio terminal MS sends Ranging Code to
the relay station RS (S180). The radio terminal MS requests
the band allocation to send the ranging request message
(RNG-REQ).
The relay station RS sends BW Req Code indicated by
the specific code to the radio base station BS (S181). This
is the same as the second embodiment. The relay station RS
request the band sufficient to send a ranging information
message (Ranging Req Msg) to the radio base station BS.
Because of the reception of the specific code, the
radio base station BS automatically allocates a
predetermined band by sending a UL-MAP message (S182), and
the relay station RS sends the ranging information message
to the radio base station BS using this allocated
predetermined band (S183).
This ranging information message includes not only
the code value of Ranging Code, Frame Index, Sub-channel and
Symbol (information to send CDMA Allocation IE), but also
correction information, level, and frequency information
(information to send a ranging response message (RNG-RSP)).
The radio base station BS extracts correction
information etc. from the ranging information message, sends
the ranging response message (RNG-RSP) to the radio terminal
MS (S184), extracts a code value etc. from the ranging
information message, and sends UL-MAP including CDMA

Allocation IE to the radio terminal MS (S185).
The radio terminal MS sends the ranging request
message (RNG-REQ) to the relay station RS using the band
allocated by UL-MAP (S186).
The radio base station BS considers a processing
delay of the relay station RS, just like the second
embodiment, and sends the UL-MAP to the relay station RS
when the delay time has elapsed (S187), and the relay
station RS sends the ranging request message (RNG-REQ) to
the radio base station BS using the band allocated by the
UL-MAP message (S188).
FIG. 19B depicts an example of information included
in the ranging response message (RNG-RSP). Such information
as timing, power level and offset frequency adjustment is
included, and this information is included in the ranging
information message (Ranging Req Msg).
In this way, operation similar to the second
embodiment can be performed by using ranging code, and band
allocation can be performed at high-speed.
The configuration of the radio base station BS and
relay station RS are the same as the second embodiment (see
FIG. 6 and FIG. 8). The specific code is generated by the
code generation unit 38, and the ranging information message
is generated and sent by the control message generation unit
36. In the radio base station BS, the ranging response
message is generated and sent by the MAP information
generation unit 16.
INDUSTRIAL APPLICABILITY
The present invention can be suitably applied to
radio communication which is performed between a radio
terminal and radio base station via a relay station.

WE CLAIM
1. A relay station (RS) for relaying communication between a radio base station
(BS) which allocates to a terminal an uplink channel for notifying a request band
when any signal sequence out of a predetermined signal sequence group is
received from the terminal, and allocates to the terminal a transmission band
according to the request band notified from the terminal via the channel, and the
terminal, comprising:
a transmission (21) unit which sends a specific signal sequence not included
in the predetermined signal sequence group, wherein
the relay station (RS) (RS) is allocated a predetermined transmission band
by the radio base station (BS), without the relation station (RS) is not allocated
the uplink channel for notifying the request band by the radio base station (BS)
which is received the specific signal sequence.
2. A radio base station (BS) for allocating to a terminal an uplink channel for
notifying a request band when any signal sequence out of a predetermined
signal sequence group is received from the terminal, and allocating a
transmission band according to the request band notified from the terminal via
the channel, comprising:
a control unit which allocates a predetermined transmission band to a relay
station (RS), without allocates the uplink channel for notifying the request band,
when a specific signal sequence not included in the predetermined signal
sequence group is received from the relay station (RS).
3. A band allocation method in a radio base station (BS) in a radio communication
system which performs radio communication between the radio base station (BS)
and a terminal via a relay station (RS), the band allocation method comprising:
allocating to the terminal a transmission band for transmitting data to the
relay station (RS), by a control unit; and

allocating to the relay station (RS) a band for transmitting the data to the
radio base station (BS), without receiving another allocation request of band
from the relay station (RS) after allocating the transmission band, by the control
unit.
4. A band allocation method in a radio base station (BS) in a radio communication
system which performs radio communication between the radio base station (BS)
and a terminal via a relay station (RS), the band allocation method comprising:
transmitting data to be transmitted to the terminal, from the radio base
station (BS) to the relay station (RS), by a transmission unit; and
allocating to the relay station (RS) a band for transmitting the data to the
terminal, without receiving transmission band allocation request from the relay
station (RS) after transmitting the data, by a control unit.
5. The band allocation method as claimed in Claim 3 or Claim 4, wherein the relay
station (RS) receives the data from the terminal or the radio base station (BS),
and a predetermined time sufficient for performing transmission processing of
the data to the radio base station (BS) or the terminal is notified from the relay
station (RS) to the radio base station (BS) using any of a ranging message, basic
function message, and registration message, which are exchanged when the
relay station (RS) and the radio base station (BS) start connection.
6. A relay station (RS) for relaying communication between a radio base station
(BS) which sends to a terminal response information to respond a signal
sequence when the radio base station (BS) receives any the signal sequence out
of a ranging signal sequence group from the terminal, and allocates to the
terminal a transmission band for ranging request, and the terminal, comprising:
a transmission unit which sends a specific signal sequence not included in
the signal sequence group, wherein

a predetermined transmission band for sending information regarding the
ranging signal sequence received from the terminal is allocated, without an
uplink channel for notifying a request band is allocated from the radio base
station (BS) on reception of the specific signal sequence.
7. A radio base station (BS) for transmitting to a terminal response information to
response a signal sequence when any the signal sequence out of ranging signal
sequence group is received from the terminal, and allocating to the terminal a
transmission band for ranging request, comprising:
a control unit which allocates to the relay station (RS) a transmission band
for transmitting information regarding the ranging signal sequence received by
the relay station (RS), without allocates an uplink channel for notifying a request
band, when receives from the relay station (RS) a predetermined signal
sequence not included in the ranging signal sequence group.
8. A band allocation method in a relay station (RS) for transmitting a message to a
radio base station (BS) which allocates an uplink channel for notifying a request
band when any signal sequence out of a predetermined signal sequence group is
received from a terminal, and allocates to the terminal a transmission band
according to the request band notified from the terminal via the uplink channel,
the band allocation method comprising:
transmitting a specific signal sequence not included in the predetermined
signal group, by a transmission unit; and
being allocated the transmission band from the radio base station (BS),
without being allocated the uplink channel for notifying the request band from
the radio base station (BS) received the specific signal sequence, by the relay
station (RS).

9. A band allocation method in a radio base station (BS) for allocating to a terminal
an uplink channel for notifying a request band when any signal sequence out of
a predetermined signal sequence group is received from the terminal, and
allocating to the terminal a transmission band according to the request band
notified from the terminal via the channel, the method comprising:
allocating a predetermined transmission band to a relay station (RS),
without allocating the uplink channel for notifying the request band, when a
specific signal sequence not included in the predetermined signal sequence
group is received from the relay station (RS), by a control unit.
10. A radio base station (BS) for performing radio communication with a terminal via
a relay station (RS), the radio base station (BS) comprising:
a control unit which allocates to the terminal a transmission band for
transmitting data to the relay station (RS), and allocates to the relay station (RS)
a band for transmitting the data to the radio base station (BS), without receiving
another allocation request of band from the relay station (RS) after allocating the
transmission band.
11. A radio base station (BS) for performing radio communication with a terminal via
a relay station (RS), the radio base station (BS) comprising:
a transmission unit which transmits to the relay station (RS) data to be
transmitted to the terminal; and
a control unit which allocates to the relay station (RS) a band for
transmitting the data to the terminal, without receiving transmission band
allocation request from the relay station (RS) after transmitting the data.
12.A band allocation method in a relay station (RS) for relaying communication
between a radio base station (BS) which sends to a terminal a response
information to respond a

signal sequence when the radio base station (BS) receives any the signal
sequence out of a ranging signal sequence group from the terminal, and
allocates to the terminal a transmission band for ranging request, and the
terminal, the method comprising:
sending a specific signal sequence not included in the signal sequence
group, by a transmission unit, wherein
a predetermined transmission band for sending information regarding the
ranging single sequence received from the terminal is allocated, without an
uplink channel for notifying a request band is allocated from the radio base
station (BS) received the specific signal sequence.
13.A band allocating method in a radio base station (BS) for transmitting to a
terminal a response information to response a signal sequence when any the
signal sequence out of ranging signal sequence group is received from the
terminal, and allocating to the terminal a transmission band for ranging request,
the method comprising:
allocating to the relay station (RS) a transmission band for transmitting
information regarding the ranging signal sequence received by the relay station
(RS), without allocating un uplink channel for notifying a request band, when
receives from the relay station (RS) a predetermined signal sequence not
included in the ranging signal sequence group, by a control unit.

ABSTRACT

RADIO BASE STATION, RELAY STATION, AND BAND ALLOCATION
METHOD
A relay station (RS) for relaying communication between a radio base
station (BS) which allocates to a terminal an uplink channel for notifying a requested
band when any signal sequence out of a predetermined signal sequence group is
received from the terminal, and allocates a transmission band according to the
requested band notified from the terminal via the channel, and the terminal,
including a transmission unit (21) which sends a specific signal sequence not
included in the predetermined signal sequence group, wherein the relation station
(RS) is allocated a predetermined transmission band by the radio base station (BS),
without the relation station (RS) is not allocated the uplink channel for notifying the
requested band by the radio base station (BS) which is received the specific signal
sequence.