Title of Invention

TRANSMITTING APPARATUS AND RADIO RESOURCE ASSIGNING METHOD

Abstract A transmission apparatus is provided with radio resource assignment means that assigns radio resources to each physical channel according to a type of the physical channel; and transmission means that transmits information to be transmitted by each physical channel using the assigned radio resources.
Full Text -1-
SPECIFICATION
TITLE OF THE INVENTION
TRANSMITTING APPARATUS AND RADIO RESOURCE ASSIGNING
METHOD
TECHNICAL FIELD
The present invention relates to a
transmission apparatus and a radio resource
assignment method.
BACKGROUND ART
In UMTS (Universal Mobile
Telecommunications System) scheme that is one of the
third generation mobile communication schemes (3G),
HSDPA (High Speed Downlink Packet Access) is
standardized as a scheme for realizing high speed
packet transmission in a link (to be referred to as
a downlink hereinafter) from a base station to a
mobile station.
In the HSDPA, for increasing throughput
that can be realized, a packet scheduling technique
is adopted in which users connecting to the base
station share radio resources (to be referred to as
a shared packet channel hereinafter), and the base
station assigns the radio resources to a user having
good propagation state on a priority basis.
In HSDPA, single carrier signal
transmission is performed in a 5MHz channel
bandwidth. Thus, the entire channel bandwidth of
5MHz is used for data that is signal-transmitted by
the shared packet channel, and assignment of
transmission slots to each user is performed based
on time multiplexing basically. In addition, also
for a control channel for reporting which user is
assigned the transmission slot and the like for
realizing this shared packet channel transmission,
signal transmission is performing using the entire

-2-
channel bandwidth of 5MHz.
On the other hand, consideration of
standardization on long term evolution (LTE) of the
UMTS is started, and study of the fourth generation
mobile communication scheme (4G) that is a mobile
communication scheme of a next generation of 3G is
being progressed. In the LTE of 3G and the 4G
schemes, it is desired to flexibly support from a
multi-cell environment such as cellular systems to
an isolated-cell environment such as hot spot areas
and indoor areas, and further desired to increase
frequency use efficiency for both of the cell
environments.
As a radio access scheme adopted for a
downlink in the LTE of 3G and the 4G schemes, it is
considered that OFDM (Orthogonal Frequency Division
Multiplexing) for transmitting signals using many
sub-carriers is a strong candidate (refer to non-
patent document 1, for example).
In the OFDM, serial to parallel conversion
is performed on a data series to be transmitted, so
that parallel signals of the data series are
transmitted using a plurality of sub-carriers.
Accordingly, since a symbol rate becomes low,
effects of delayed waves (multi-path) caused due to
difference of propagation routes from a transmitter
to a receiver is suppressed, so that it becomes
possible to transmit a signal of high information
rate with high quality.
In addition, for supporting the multi-cell
environment by the radio access scheme using the
OFDM, it is desirable to apply one-cell frequency
reuse for realizing large capacity. For realizing
the one-cell frequency reuse, application of
spreading is effective to suppress effects of
interference signals using the same frequency from
surrounding adjacent cells.

-3-
Thus, in OFDM (OFDM with Spreading) to
which spreading is applied, as shown in Figs.lA and
1B, after the input data is channel-coded and data-
modulated, spreading is applied, and serial to
parallel conversion and inverse Fourier conversion
are performed, so that signals of multi-carriers are
generated and are transmitted after a guard interval
is inserted. More particularly, as a case where
spreading is applied, when 8 is applied as a
spreading factor for example, each symbol is spread
into eight sub-carries and is transmitted. In
addition, when effects of interference from
surrounding cells are small, 1 is applied as a
spreading factor since it is unnecessary to apply
spreading, so that data D1, D2, ... that are
different in each sub-carrier are transmitted.
Also in OFDM or OFDM to which spreading is
applied as mentioned above, the packet scheduling
technique can be applied using a shared channel like
one used in HSDPA, and throughput can be increased
accordingly. In this case, since multi-carrier
transmission is performed in OFDM for shared channel
transmission, not only a method for performing
transmission slot assignment to each user by time
multiplexing like HSDPA is available but also it is
available to assign radio resources to each user in
units of a sub-carrier or in units of a frequency
block in which a plurality of sub-carriers are bound
(refer to non-patent document 2, for example).
Therefore, when performing signal
transmission using multi-carrier transmission within
a channel bandwidth, a method for assigning radio
resources different from one for HSDPA becomes
possible.
However, in order to realize actual mobile
communication in OFDM or OFDM using spreading, in
addition to transmitting the shared channel, it is

-4-
necessary to transmit a control channel necessary
for transmitting control information of the shared
channel or transmit a common control channel for
transmitting system information and paging
information that are transmitted to all users
connected to a base station.
[Non-patent document 1] J. A. C. Bingham,
"Multicarrier modulation for data transmission: an
idea whose time has come," IEEE Commun. Mag., pp. 5-
14, May 1990.
[Non-patent document 2] W. Wang, T. Ottosson, M.
Sternad, A. Ahlen, A. Svensson, "Impact of multiuser
diversity and channel variability on adaptive OFDM,"
IEEE VTC2003-Fall, pp.547-551, Oct. 2003.
DISCLOSURE OF THE INVENTION
PROBLEM TO BE SOLVED BY THE INVENTION
However, in the above-mentioned multi-
carrier transmission for performing signal
transmission using a plurality of sub-carriers,
there is a following problem.
There is a problem, in a downlink, that it
is not determined that how radio resources are
optimally assigned to physical channels for
transmitting different types of information.
An object of the present invention is to
provide a transmission apparatus and a radio
resource assignment method that can assign radio
resources according to types of physical channels.
MEANS FOR SOLVING THE PROBLEM
To solve the above problem, a
transmission apparatus, as one feature, includes:
radio resource assignment means that
assigns radio resources to each physical channel
according to a type of the physical channel; and
transmission means that transmits

-5-
information to be transmitted by each physical
channel using the assigned radio resources.
By adopting a configuring like this, radio
resources can be assigned according to types of
physical channels.
As to a radio resource assignment method
of the present invention, a radio resource
assignment method in a transmission apparatus for
transmitting a plurality of sub-carriers, as one
feature, includes:
a step of receiving information indicating
receiving quality;
a step of determining a user for
transmission based on the receiving quality;
a step of assigning radio resources to
each physical channel according to a type of the
physical channel; and
a step of transmitting information to be
transmitted by each physical channel using the
assigned radio resources to the user.
Accordingly, radio resources can be
assigned according to types of physical channels so
that information to be transmitted by each physical
channel can be transmitted to users.
EFFECT OF THE INVENTION
According to an embodiment of the present
invention, a transmission apparatus and a radio
resource assignment method that can assign radio
resources according to types of physical channels
can be realized.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig.1A is an explanatory diagram showing
an OFDM communication scheme to which spreading is
applied;
Fig.1B is an explanatory diagram showing

-6-
an OFDM communication scheme to which spreading is
applied;
Fig.2 is an explanatory diagram showing
classification of physical channels;
Fig.3 is a block diagram showing a
transmission apparatus of an embodiment of the
present invention;
Fig.4 is an explanatory diagram showing
combinations of receiving quality levels, data
modulation schemes and coding rates;
Fig.5 is an explanatory diagram showing
radio resource assignment to a common control
channel, a control signaling channel and a shared
channel;
Fig.6A is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6B is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6C is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6D is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6E is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6F is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6G is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6H is an explanatory diagram showing
radio resource assignment to the common control

-7-
channel;
Fig.6I is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6J is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6K is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.6L is an explanatory diagram showing
radio resource assignment to the common control
channel;
Fig.7A is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7B is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7C is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7D is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7E is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7F is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7G is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7H is an explanatory diagram showing
radio resource assignment to the control signaling
channel;

Fig.71 is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7J is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7K is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.7L is an explanatory diagram showing
radio resource assignment to the control signaling
channel;
Fig.8 is a block diagram showing a
transmission apparatus of an embodiment of the
present invention;
Fig.9A is an explanatory diagram showing
an application example of time multiplexing;
Fig.9B is an explanatory diagram showing
an application example of time multiplexing;
Fig.10 is a block diagram showing a
transmission apparatus of an embodiment of the
present invention;
Fig.11A is an explanatory diagram showing
an example of combined use of frequency
multiplexing;
Fig.11B is an explanatory diagram showing
an example of combined use of frequency
multiplexing;
Fig. 12 is a block diagram showing a
transmission apparatus of an embodiment of the
present invention;
Fig.13 is an explanatory diagram showing
an application example of code multiplexing;
Fig.14 is an explanatory diagram showing
radio resource assignment to the shared channel;
Fig.15 is an explanatory diagram showing
radio resource assignment to the shared channel;

-9-
Fig.16 is an explanatory diagram showing
radio resource assignment to the shared channel;
Fig.l7A is an explanatory diagram showing
radio resource assignment to the shared channel;
Fig.l7B is an explanatory diagram showing
radio resource assignment to the shared channel;
Fig.18 is an explanatory diagram showing
radio resource assignment to a multicast channel and
other physical channels;
Fig.19 is an explanatory diagram showing
multiplexing of high data rate users;
Fig.20 is an explanatory diagram showing
multiplexing of low data rate users;
Fig.21 is an explanatory diagram showing
multiplexing of low data rate users;
Fig.22A is an explanatory diagram showing
multiplexing of users of high speed mobility;
Fig.22B is an explanatory diagram showing
multiplexing of users of high speed mobility;
Fig.23A is an explanatory diagram showing
multiplexing of users of low speed mobility;
Fig.23B is an explanatory diagram showing
multiplexing of users of low speed mobility;
Fig.24 is an explanatory diagram showing
multiplexing of low data rate users;
Fig.25A is an explanatory diagram showing
multiplexing of low data rate users;
Fig.25B is an explanatory diagram showing
multiplexing of low data rate users;
Fig.26A is an explanatory diagram showing
multiplexing of low data rate users;
Fig.26B is an explanatory diagram showing
multiplexing of low data rate users;
Fig.27A is an explanatory diagram showing
multiplexing of low data rate users;
Fig.27B is an explanatory diagram showing
radio resource assignment to the shared channel;

-10-
Fig.28 is a flowchart showing operation of
a transmission apparatus of an embodiment of the
present invention.
Description of reference signs
100 transmission apparatus
PREFERRED EMBODIMENTS FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention
are described with reference to drawings. By the
way, in all drawings for explaining the embodiments,
same reference signs are used for units having same
function, and repeated description is not given.
First, a physical channel in the downlink
intended for embodiments of the present invention is
described with reference to Fig.2.
The physical channel in the downlink
intended for the embodiments of the present
invention is classified into a common control
channel, a shared channel, a channel (to be referred
to as control signaling channel, hereinafter) for
transmitting control information of the physical
layer and control information of the layer 2, and a
multicast channel.
The common control channel is a channel
for performing transmission for the whole of a cell
covered by a base station, for example, the common
control channel transmits broadcast information,
paging information and the like.
The shared channel is for transmitting
traffic data to each user, control signal data using
a signal of an upper layer and the like. For
example, as the control signal using the signal of
the upper layer, there is ACK/NACK indicating
presence or absence of a receiving error in TCP/IP.
The control signaling channel transmits,
as control information in the physical layer,

-11-
information of modulation scheme and coding rate in
adaptive modulation, for example. In addition, the
control signaling channel transmits, as control
information of the physical layer, radio resource
assignment information such as information
indicating which symbol or sub-carrier is assigned,
for example.
In addition, the control signaling channel
transmits, as control information of the layer 2,
information of packet retransmission control, for
example. In addition, the control signaling channel
transmits, as control information of the layer 2,
assignment information of packet scheduling, for
example.
The multicast channel is a channel for
multicast.
A transmission apparatus of an embodiment
of the present invention is described with reference
to Fig.3.
The transmission apparatus is provided in
a base station, for example, and transmits a
downlink channel.
The transmission apparatus 100 transmits
the common control channel and the control signaling
channel using an entire frequency band or at least a
part of frequency bands discretely located over the
entire frequency band. Accordingly, diversity
effect can be obtained in a frequency domain.
In addition, the transmission apparatus
100 divides a time domain and a frequency domain,
and transmits the shared channel based on packet
scheduling for assigning a part corresponding to
good receiving status to a user. Accordingly, multi
-user diversity effect can be obtained.
In addition, the transmission apparatus
100 may transmit the shared channel based on packet
scheduling of the time domain using the entire

-12-
channel band. Accordingly, frequency diversity
effect can be obtained.
The transmission apparatus 100 includes a
common control channel signal generation unit 110, a
control signaling channel signal generation unit 120,
a shared channel signal generation unit 130, a radio
resource assignment unit 140 connected to the common
control channel signal generation unit 110, the
control signaling channel generation unit 120 and
the shared channel signal generation unit 130, an
IFFT unit 150 connected to the radio resource
assignment unit 140, and a guard interval inserting
unit 160 connected to the IFFT unit 150.
The common control channel signal
generation unit 110 includes a channel coding unit
102 to which transmission data sent by the common
control channel is supplied, a data modulation unit
104 connected to the channel coding unit 102, and a
spreading unit 106 connected to the data modulation
unit 104. The spreading unit 106 is connected to
the radio resource assignment unit 140.
The shared channel signal generation unit
130 includes a packet scheduling unit 128 to which
data from each user is supplied, a channel coding
unit 122 connected to the packet scheduling unit 128,
a data modulation unit 124 connected to the channel
coding unit 122, and a spreading unit 124 connected
to the data modulation unit 124. The spreading unit
126 is connected to the radio resource assignment
unit 140.
The control signaling channel signal
generation unit 120 includes a channel coding unit
112 connected to the packet scheduling unit 128 as a
scheduling means, a data modulation unit 114
connected to the channel coding unit 112, a
spreading unit 116 connected to the data modulation
unit 114. The spreading unit 116 is connected to

-13-
the radio resource assignment unit 140.
Data from each user is supplied to the
packet scheduling unit 128. In the packet
scheduling unit 128, packet scheduling is performed
for selecting a user to be assigned to the shared
channel based on feedback information indicating
radio status sent from each user (receiving station).
For example, the packet scheduling unit 128 divides
the time domain and the frequency domain to assign a
part where the radio status is good to a user.
In addition, the packet scheduling unit
128 determines a channel coding rate and a data
modulation scheme for the selected user. In
addition, the packet scheduling unit 128 determines
a spreading factor for the selected user. For
example, the packet scheduling unit 128 determines
the data modulation scheme and the data coding rate
based on information indicating data modulation
schemes and coding rates for receiving quality
levels shown in Fig.4 so as to perform transmission
most efficiently according to an algorithm set
beforehand.
The information indicating the data
modulation schemes and the coding rates for the
receiving quality levels are defined such that, the
better the receiving quality level is, the greater a
modulation level of the data modulation scheme is
and the larger the coding rate is. For example, as
the data modulation scheme, QPSK, 16QAM, and QAM are
defined as the receiving quality becomes better. As
the coding rate, increasing values form 1/9 to 3/4
are defined as the receiving quality level becomes
better. The data modulation scheme and the coding
rate defined here are changed according to an
environment, cell and the like where the
transmission apparatus is installed.
In addition, the packet scheduling unit

-14-
128 supplies, to the channel coding unit 112, the
data modulation unit 124 and the spreading unit 126,
information obtained by packet scheduling that is,
for example, a user ID indicating a selected user
and information, as control information, indicating
at least one of a spreading factor to be used for
transmission for the user, a channel coding rate and
a data modulation scheme.
In addition, the packet scheduling unit
128 supplies transmission data of a user selected by
the packet scheduling to the channel coding unit 122,
and the information is supplied to the data
modulation unit 124.
The channel coding unit 122 performs
channel coding on the transmission data according to
the channel coding rate selected by the packet
scheduling unit and supplies the transmission data
to the data modulation unit 124.
The data modulation unit 124 performs data
modulation on the transmission data on which channel
coding has been performed according to the data
modulation scheme selected by the packet scheduling
unit 128, and supplies the data to the spreading
unit 126.
The spreading unit 126 spreads the
transmission data on which data modulation has been
performed with the spreading factor selected by the
packet scheduling unit 128, and supplies the data to
the radio resource assignment unit 140.
On the other hand, control information
supplied to the channel coding unit 112 by the
packet scheduling unit 128 is channel-coded
according to a channel coding rate set beforehand in
the channel coding unit 112, and the control
information is supplied to the data modulation unit
114.
The data modulation unit 114 performs data

-15-
modulation on the control information to which
channel coding has been performed according to a
data modulation scheme set beforehand, and supplies
the control information to the spreading unit 116.
The spreading unit 116 spreads the control
information on which data modulation has been
performed according to the spreading factor set
beforehand, and supplies the control information to
the radio resource assignment unit 140.
In addition, information transmitted by
the common control channel is supplied to the
channel coding unit 102, so that channel coding is
performed according to a channel coding rate set
beforehand, and the information is supplied to the
data modulation unit 104.
The data modulation unit 104 performs data
modulation on transmission data on which channel
coding has been performed, and supplies the
transmission data to the spreading unit 106.
The spreading unit 116 spreads the
transmission data on which data modulation has been
performed according to a spreading factor set
beforehand, and supplies the transmission data to
the radio resource assignment unit 140.
The channel coding rate used by the
channel coding units 102 and 112, the data
modulation schemes used by the data modulation units
104 and 114, and the spreading factors used by the
spreading units 106 and 116 are changeable according
to an environment and a cell (sector).
The radio resource assignment unit 140
assigns radio resources to the common control
channel, the control signaling channel and the
shared channel.
Descriptions are provided with reference
to Fig.5.
For example, when assigning radio

-16-
resources to the common control channel and the
control signaling channel, as shown in configuration
1, the radio resource assignment unit 140 divides an
entire frequency band assigned to the system into
sub-carrier blocks each formed by one or more sub-
carriers, and assigns at least a sub-carrier block
to a transmission slot indicating a unit (TTI:
Transmission Time Interval) of packet transmission.
In addition, when assigning radio
resources to the shared channel, the radio resource
assignment unit 140 assigns radio resources other
than those assigned to the common control channel
and the control signaling channel. Accordingly, as
to the common control channel and the control
signaling channel, mapping to discrete frequency
domains over the entire frequency band is performed,
so that receiving quality in the receiver can be
improved due to frequency diversity effect.
In addition, as shown in configuration 2,
when assigning radio resources to the common control
channel and the control signaling channel, the radio
resource assignment unit 140 may assign, to the
common control channel and the control signaling
channel, at least a part of a plurality of symbols
forming the transmission slot that indicates the
unit (TTI: Transmission Time Interval) of
transmission in packet transmission.
Also in this case, when assigning radio
resources to the shared channel, the radio resource
assignment unit 140 assigns symbols other than the
symbols to which the common control channel or the
control signaling channel is assigned. Accordingly,
since the common control channel and the control
signaling channel can be mapped over the entire
frequency band, receiving quality of the receiver
can be improved due to frequency diversity effect.
In addition, as shown in configuration 3,

-17-
when assigning radio resources to the common control
channel and the control signaling channel, the radio
resource assignment unit 140 divides the entire
frequency band assigned to the system into sub-
carrier blocks each formed by one or more sub-
carriers in the frequency axis direction, and
divides in units of a plurality of OFDM symbols in
the time axis direction, so as to form frequency
blocks using a plurality of sub-carriers and a
plurality of OFDM symbols.
The radio resource assignment unit 140 may
select at least one of a plurality of frequency
blocks to assign it to the common control channel
and the control signaling channel. In addition, the
radio resource assignment unit 140 may assign at
least a part of a plurality of OFDM symbols forming
the frequency block to the common control channel
and the control signaling channel.
Also in this case, when assigning the
radio resources to the shared channel, the radio
resource assignment unit 140 may assign at least one
of symbols and frequency blocks other than symbols
assigned to the common control channel and the
control signaling channel. Accordingly, since the
common control channel and the control signaling
channel can be mapped to discrete frequency domains
in the entire frequency band, receiving quality in
the receiver can be improved due to the frequency
diversity effect.
The IFFT unit 150 performs inverse fast
Fourier transform on the input signal to perform
modulation of the OFDM scheme.
The GI adding unit 160 adds a guard
interval to a signal to be transmitted to generate a
symbol of the OFDM scheme. The guard interval is
obtained by copying a part of a head or an end of a
symbol to be transmitted.

-18-
In the following, assignment of radio
resources is described concretely for each of the
common control channel, the control signaling
channel and the shared channel.
First, radio resource assignment for the
common control channel is described with reference
to Figs.6A-6L.
The common control channel is information
directed to all users in a cell. In addition, it is
necessary that the users in the cell can receive the
information with required spatial probability and
with required quality, for example, with a
predetermined error rate. Thus, when transmission
is performed using only a narrow frequency band in
the entire frequency band, receiving status in the
frequency is different for each user and there is a
risk that there occurs a user for whom receiving
status is bad depending on circumstances. In
addition, since the information is directed to all
users, usage of performing assignment with packet
scheduling to perform signal transmission is not
possible.
Therefore, in the common control channel,
packet scheduling is not applied, and the channel is
assigned to the entire frequency band or at least a
part of frequency bands discretely placed over the
entire frequency band. Accordingly, frequency
diversity effect can be obtained.
For example, when assigning radio
resources to the common control channel, as shown in
Fig.6A, the common control channel is assigned to at
least one transmission slot, and transmission is
performed using the entire frequency band in the
assigned transmission slot. By using the entire
frequency band in this way, receiving quality in the
receiver can be improved due to frequency diversity
effect.

-19-
In addition, when assigning radio
resources to the common control channel, as shown in
Fig.6B, the entire frequency band assigned to the
system is divided into sub-carrier blocks each
formed by a plurality of sub-carriers, and the
common control channel is sequentially mapped to at
least one of the sub-carrier blocks. By performing
mapping in the frequency direction in this way,
receiving quality in the receiver can be improved
due to frequency diversity effect.
In addition, when assigning radio
resources to the common control channel, as shown in
Fig.6C, the configurations 1 and 2 are combined so
that the common control channel is mapped to at
least one sub-carrier block in at least one
transmission slot. By performing mapping in the
frequency direction in this way, receiving quality
in the receiver can be improved due to frequency
diversity effect.
In addition, when assigning radio
resources to the common control channel, as shown in
Fig.6D, the common control channel is assigned to a
part of symbols in at least one transmission slot,
and transmission is performed using the entire
frequency band in the symbol to which assignment is
performed. Accordingly, by using the entire
frequency band, receiving quality in the receiver
can be improved due to frequency diversity effect.
In addition, when assigning radio
resources to the common control channel, as shown in
Fig.6E, the entire frequency band assigned to the
system is divided into sub-carrier blocks each
formed by a plurality of sub-carriers, and the
common control channel is sequentially mapped to a
part of sub-carriers in at least one sub-carrier
block. By performing mapping in the frequency
direction in this way, receiving quality in the

-20-
receiver can be improved due to frequency diversity
effect.
In addition, when assigning radio
resources to the common control channel, as shown in
Fig.6F, the configurations 3 and 4 are combined to
map the common control channel into a part of sub-
carriers in at least one sub-carrier block in a part
of symbols in at least one transmission slot. By
performing mapping in the frequency direction in
this way, receiving quality in the receiver can be
improved due to frequency diversity effect.
In addition, when assigning radio
resources to the common control channel, as shown in
Fig.6G, the common control channel is mapped to a
part of symbols in at least one sub-carrier block in
at least one transmission slot. In this case, in
each transmission slot, the common control channel
to be mapped is placed such that the position is
different in at least a part of sub-carrier blocks.
By mapping the common control channel in the
frequency direction and the time axis direction in
this way, receiving quality in the receiver can be
improved due to time diversity effect in addition to
the frequency diversity effect. For example, when
the receiver is moving at high speed, there is a
case where receiving quality in a frequency falls
down at a certain instant. In such a case, by
performing mapping such that the position of the
common control channel to be mapped to each sub-
carrier block is different in at least a part of
sub-carrier blocks, the time diversity effect can be
obtained so that receiving quality can be improved.
In addition, as shown in Fig.6H, when
assigning the radio resources to the common control
channel, the transmission slot described in Fig.6G
may be transmitted a predetermined number of times
at intervals of a predetermined time. Accordingly,

-21-
by transmitting a same transmission slot a plurality
of number of times, receiving quality in the
receiver can be improved due to the time diversity
effect in addition to the frequency diversity effect.
In this case, the time interval by which the
transmission slot is sent is adaptively controlled
according to the environment. For example, the
transmission interval is set to be long in an
environment like an office where movement is small,
and the transmission interval is set to be short in
an environment like a city where movement is large.
In addition, mapping may be performed such that a
position of the common control channel to be mapped
to a part of symbols of at least one sub-carrier
block in a transmission slot to be transmitted
secondly or later is different from a position of
previously transmitted common control channel.
The position of the common control channel
in each sub-carrier block described in Figs.6G and
6H is determined fixedly beforehand based on a
predetermined rule as shown in Fig.61. In addition,
the position of the common control channel in each
sub-carrier block may be randomly determined in each
sub-carrier block as shown in Fig.6J.
In addition, in Fig.6H, as shown in Fig.6K,
information same as one transmitted first is
transmitted by the common control channel
transmitted secondly or later. In this case,
demodulation processing is performed in the receiver,
and it is determined whether there is a demodulation
error. When there is no demodulation error, the
receiver is controlled such that it does not receive
the common control channel transmitted secondly or
later. When there is a demodulation error, the
information is discarded, and the common control
channel transmitted secondly or later is demodulated
again (no packet combining, Type-I).

-22-
In addition, as shown in Fig.6L, when
there is a demodulation error, the information may
not be discarded so as to perform packet combining
for the common control channel transmitted secondly
or later and the common control channel received
previously to demodulate again (packet combining
exists, Type-I). Accordingly, receiving SIR can be
improved.
In addition, in Fig.6H, the common control
channel transmitted secondly or later may be for
transmitting information different from one in the
first transition. For example, the common control
channel transmitted secondly or later may be
configured to transmit a packet on which puncturing
is performed with a pattern different from a pattern
for the first transmission (packet combining exists,
Type-II). In this case, demodulation processing is
performed in the receiver side, and it is determined
whether there is a demodulation error. When there
is no demodulation error, the receiver is controlled
such that it does not receive the common control
channel transmitted thirdly or later. When there is
a demodulation error, the information may not be
discarded, and packet combining may be performed for
the common control channel transmitted secondly or
later and the common control channel received
previously to demodulate again. Accordingly, coding
gain can be improved.
In addition, in Fig.6H, the common control
channel transmitted secondly or later may be
configured to transmit information different from
one sent first. For example, information indicating
the common control channel is divided into two or
more, and the divided information is transmitted.
When information is stored in the common control
channel transmitted first and redundancy code is
stored in the common control channel transmitted

-23-
secondly or later, the common control channel
transmitted secondly or later cannot be decoded when
receiving of the common control channel transmitted
first is failed.
In such a case, by dividing information
indicating the common control channel into two or
more, receiving quality in the receiver can be
improved due to time diversity effect. In this case,
a transmission slot for transmitting information
indicating the common control channel by dividing it
and a packet storing the redundancy code may be
transmitted.
In this case, it is necessary to determine
a number of division of the common control channel
beforehand in the transmitter and the receiver. As
information to be determined beforehand, a packet
number for performing packet combining, a puncture
pattern, constellation, and a bit indicating new or
retransmitted packet are necessary. The bit
indicating a new or retransmitted packet is
necessary for avoiding incorrect combining
considering ACK/NACK bit error.
Next, assignment of radio resources to the
control signaling channel is described with
reference to Figs.7A-7L.
The control signaling channel is a signal
transmitted for each user scheduled by the packet
scheduling unit 128, and it is necessary for
specific many users who desire scheduling in the
cell to be able to receive the signal with a
required spatial probability and a required quality,
that is, with a predetermined error rate, for
example. Therefore, the channel is assigned to the
entire frequency band or at least a part of the
entire frequency band that is discretely located
over the entire frequency band without applying
packet scheduling. Accordingly, frequency diversity

-24-
effect can be obtained.
For example, as shown in Fig.7A, when
assigning radio resources to the control signaling
channel, the control signaling channel is assigned
to at least one transmission slot, and transmission
is performed using all of the entire frequency band
in the assigned transmission slot. By using the
entire frequency band in this way, receiving quality
in the receiver can be improved due to frequency
diversity effect.
In addition, as shown in Fig.7B, when
assigning the radio resources to the control
signaling channel, the entire frequency band
assigned to the system is divided into sub-carrier
blocks each formed by a plurality of sub-carriers so
that the control signaling channel is mapped
sequentially to at least one sub-carrier block. By
performing mapping in the frequency direction in
this way, receiving quality in the receiver can be
improved due to the frequency diversity effect.
In addition, as shown in Fig.7C, when
assigning the radio resources to the control
signaling channel, Fig.7A and Fig.7B are combined so
that the control signaling channel is mapped to at
least one sub-carrier block in at least one
transmission slot. By performing mapping in the
frequency direction in this way, receiving quality
in the receiver can be improved due to frequency
diversity effect.
In addition, when assigning radio
resources to the control signaling channel, as shown
in Fig.7D, the control signaling channel is assigned
to a part of symbols in at least one transmission
slot, and transmission is performed using the entire
frequency band in the symbol to which assignment is
performed. By using the entire frequency band in
this way, receiving quality in the receiver can be

-25-
improved due to frequency diversity effect.
In addition, when assigning radio
resources to the control signaling channel, as shown
in Fig.7E, the entire frequency band assigned to the
system is divided into sub-carrier blocks each
formed by a plurality of sub-carriers, and the
control signaling channel is sequentially mapped to
a part of sub-carriers in at least one sub-carrier
block. By performing mapping in the frequency
direction in this way, receiving quality in the
receiver can be improved due to frequency diversity
effect.
In addition, when assigning radio
resources to the control signaling channel, as shown
in Fig.7F, Fig.7C and Fig.7D are combined to map the
control signaling channel into a part of sub-
carriers in at least one sub-carrier block in a part
of symbols in at least one transmission slot. By
performing mapping in the frequency direction in
this way, receiving quality in the receiver can be
improved due to frequency diversity effect.
In addition, when assigning radio
resources to the control signaling channel, as shown
in Fig.7G, the control signaling channel is mapped
to a part of symbols in at least one sub-carrier
block in at least one transmission slot. In this
case, in each transmission slot, the control
signaling channel to be mapped is placed such that
the position is different in at least a part of sub-
carrier blocks. By mapping the control signaling
channel in the frequency direction and the time axis
direction in this way, receiving quality in the
receiver can be improved due to time diversity
effect in addition to the frequency diversity effect
For example, when the receiver is moving at high
speed, there is a case where receiving quality in a
frequency falls down at a certain instant. In such

-26-
a case, by performing mapping such that the position
of the control signaling channel to be mapped to
each sub-carrier block is different in at least a
part of sub-carrier blocks, the time diversity
effect can be obtained so that receiving quality can
be improved.
In addition, as shown in Fig.7H, when
assigning the radio resources to the control
signaling channel, the transmission slot described
in Fig.7G may be transmitted a predetermined number
of times at intervals of a predetermined time. By
transmitting a same transmission slot a plurality of
number of times in this way, receiving quality in
the receiver can be improved due to the time
diversity effect in addition to the frequency
diversity effect. In this case, the time interval
by which the transmission slot is sent is adaptively
controlled according to the environment. For
example, the transmission interval is set to be long
in an environment like an office where movement is
small, and the transmission interval is set to be
short in an environment like a city where movement
is large. In addition, mapping may be performed
such that a position of the control signaling
channel to be mapped to a part of symbols of at
least one sub-carrier block in a transmission slot
to be transmitted secondly or later is different
from a position of previously transmitted control
signaling channel.
The position of the control signaling
channel in each sub-carrier block described in
Figs.7G and 7H is determined fixedly beforehand
based on a predetermined rule as shown in Fig.71.
In addition, the position of the control signaling
channel in each sub-carrier block may be randomly
determined in each sub-carrier as shown in Fig.7J.
In addition, in Fig.7H, as shown in Fig.7K,

-27-
information same as one transmitted first is
transmitted by the control signaling channel
transmitted secondly or later. In this case,
demodulation processing is performed in the receiver,
and it is determined whether there is a demodulation
error. When there is no demodulation error, the
receiver is controlled such that it does not receive
the control signaling channel transmitted secondly
or later. When there is a demodulation error, the
information is discarded, and the control signaling
channel transmitted secondly or later is demodulated
again (no packet combining, Type-I).
In addition, as shown in Fig.7L, when
there is a demodulation error, the information may
not be discarded so as to perform packet combining
for the control signaling channel transmitted
secondly or later and the control signaling channel
received previously to demodulate again (packet
combining exists, Type-I). Accordingly, receiving
SIR can be improved.
In addition, in Fig.7H, the control
signaling channel transmitted secondly or later may
be for transmitting information different from one
in the first transition. For example, the control
signaling channel transmitted secondly or later may
be configured to transmit a packet on which
puncturing is performed with a pattern different
from a pattern for the first transmission (packet
combining exists, Type-II). In this case,
demodulation processing is performed in the receiver
side, and it is determined whether there is a
demodulation error. When there is no demodulation
error, the receiver is controlled such that it does
not receive the control signaling channel
transmitted thirdly or later. When there is a
demodulation error, the information may not be
discarded, and packet combining may be performed for

-28-
the control signaling channel transmitted secondly
or later and the control signaling channel received
previously to demodulate again. Accordingly, coding
gain can be improved.
In addition, in Fig.7H, the control
signaling channel transmitted secondly or later may
be configured to transmit information different from
one sent first. For example, information indicating
the control signaling channel is divided into two or
more, and the divided information is transmitted.
When information is stored in the control signaling
channel transmitted first and redundancy code is
stored in the control signaling channel transmitted
secondly or later, the control signaling channel
transmitted secondly or later cannot be decoded when
receiving of the control signaling channel
transmitted first is failed.
In such a case, by dividing information
indicating the control signaling channel into two or
more, receiving quality in the receiver can be
improved due to time diversity effect. In this case,
a transmission slot for transmitting information
indicating the control signaling channel by dividing
it and a packet storing the redundancy code may be
transmitted.
In this case, it is necessary to determine
a number of division of the control signaling
channel beforehand in the transmitter and the
receiver. As information to be determined
beforehand, a packet number for performing packet
combining, a puncture pattern, constellation, and a
bit indicating new or retransmitted packet are
necessary. The bit indicating a new or
retransmitted packet is necessary for avoiding
incorrect combining considering ACK/NACK bit error.
As mentioned above, cases where radio
resources are assigned to the common control channel

-29-
and the control signaling channel are described so
far.
Next, a method for assigning radio
resources to a plurality of common control channels
and control signaling channels is described.
In this embodiment, descriptions are
provided for each of a case where time multiplexing
is applied, a case where frequency multiplexing is
additionally used and a case where code multiplexing
is additionally used.
First, a case where time multiplexing is
applied is described.
In this case, as shown in Fig.8, the
transmission apparatus is configured by a common
control channel signal generation unit 110 to which
transmission data to be transmitted by the common
control channel as a channel #1 is supplied, a
control signaling channel signal generation unit 120
to which control information is supplied from the
packet scheduling unit 128 as a channel #2, a radio
resource assignment unit 140, an IFFT unit 150 and a
guard interval insertion unit 160.
The radio resource assignment unit 140
includes a switching unit 131 connected to spreading
units 106 and 116, a switching control unit 132 and
a serial to parallel conversion unit 133 connected
to the switching unit 131. The serial to parallel
conversion unit 133 is connected to the IFFT unit
150.
The switching control unit 132 performs
control so as to switch channels to be transmitted
for each symbol or each transmission slot. The
switching unit 131 timely switches channels to be
transmitted according to a control signal from the
switching control unit 132 to supply signals to the
serial to parallel conversion unit 133.
For example, as shown in Fig.9A, the

-30-
switching control unit 132 divides the time domain
into a plurality of domains in an assigned frequency
block, and performs switching so as to assign
physical channels of a plurality of common control
channels and control signaling channels in the
divided time domains. For example, the switching
control unit 132 performs switching so as to assign
a plurality of physical channels of the common
control channels and the control signaling channels
in units of symbols included in the divided time
domains, for example, for each of channels #1, #2,
#3, ... .
In this case, radio resources to which any
of the common control channel and the control
signaling channel is not assigned are assigned
another physical channel such as an after-mentioned
shared channel, for example.
Accordingly, by using at least one
frequency block and by assigning a plurality of
common control channels and the control signaling
channels at a symbol level, receiving quality can be
improved due to frequency diversity effect.
In addition, for example, as shown in
Fig.9B, the switching control unit 134 may perform
switching, for each transmission slot, so as to
assign a plurality of physical channels, as channels
#1, #2, for example, including the common control
channels, the control signaling channels or both of
them to a predetermined OFDM symbol of frequency
blocks included in the transmission slot.
In this case, radio resources to which any
of the common control channel and the control
signaling channel is not assigned are assigned
another physical channel such as an after-mentioned
shared channel, for example. Accordingly, by
assigning a plurality of common control channels,
control signaling channels or both of them, the

-31-
common control channels and the control signaling
channels can be transmitted using the entire band,
so that receiving quality can be improved due to
frequency diversity effect.
Next, a case where frequency multiplexing
is used together is described. In this case, a
transmission method is described in a case where the
frequency multiplexing is used together with the
time multiplexing when the number of physical
channels that can be multiplexed is small by
applying only the before-mentioned time multiplexing.
The transmission apparatus in the case
where frequency multiplexing is used together is
different from the transmission apparatus described
with reference Fig.8 in that the configuration of
the radio resource assignment unit 140 is different.
The radio assignment unit 140 includes a sub-carrier
mapping unit 134 connected to spreading units 106
and 116, and a sub-carrier mapping control unit 135
connected to the sub-carrier mapping unit 134. The
sub-carrier mapping unit 134 is connected to the
IFFT unit 150.
The sub-carrier mapping control unit 135
determines sub-carriers for mapping common control
channels and control signaling channels, and
supplies the result to the sub-carrier mapping unit
134. The sub-carrier mapping unit 134 performs
mapping for the common control channels and control
signaling channels based on the supplied information
on the sub-carriers.
For example, as shown in Fig.llA, the sub-
carrier mapping control unit 135 divides a frequency
band of each frequency block into a plurality of
bands to assign the common control channels and the
control signaling channels in units of divided band.
Further, the sub-carrier mapping control unit 135
may divide the time domain of the frequency blocks

-32-
into a plurality of domains to change the common
control channels and the control signaling channels
to be assigned to each divided time domain in a time
division manner.
For example, when dividing a frequency
band in each of selected frequency blocks into two
bands and dividing a transmission slot into three,
the sub-carrier mapping control unit 135 assigns the
common control channels, control signaling channels
or both of them to the divided blocks, for example,
to channels #1, #2, #3, ... #6.
By using a plurality of frequency blocks
in this way, and by assigning the common control
channels and the control signaling channels to
bands divided from the frequency band in each
frequency block, the receiving quality in the
receiver can be improved due to frequency diversity
effect.
In addition, for example, as shown in
Fig.llB, the sub-carrier mapping control unit 135
may assign, at a transmission slot level, the common
control channels, the control signaling channels or
both of them to a predetermined OFDM symbol of
frequency blocks included in the transmission slot,
as channels #1, #2, #3, and #4 for example.
For example, the sub-carrier mapping
control unit 135 assigns the common control channels,
the control signaling channels or both of them to a
predetermined OFDM symbol in assigned frequency
blocks. In this case, radio resources to which any
of the common control channel and the control
signaling channel is not assigned are assigned
another physical channel such as an after-mentioned
shared channel, and switching is performed in a time
division manner.
Accordingly, by assigning the common
control channels, the control signaling channels or

-33-
both of them at the frequency block level, the
common control channels and the control signaling
channels can be transmitted using discrete parts
over the entire band, so that receiving quality can
be improved due to frequency diversity effect.
Next, a case where code multiplexing is
used together is described.
The transmission apparatus in the case
where code multiplexing is used together is
different from the transmission apparatus described
with reference to Fig.8 in that the configuration of
the radio resource assignment unit 140 is different.
The radio assignment unit 140 includes a code
multiplexing unit 137 connected to spreading units
106 and 116, and a code multiplexing control unit
136 connected to the code multiplexing unit 137.
The code multiplexing unit 137 is connected to the
IFFT unit 150.
The code multiplexing control unit 136
performs control for code-multiplexing output
signals, from the spreading units 106 and 116, that
are spread with different spreading codes. The code
multiplexing unit 137 performs code multiplexing on
input channels.
For example, as shown in Fig.13, the code
multiplexing control unit 136 assigns each of the
common control channels, the control signaling
channels or both of them as channels #1, #2 for
example, to a predetermined OFDM symbol in OFDM
symbols included in a transmission slot at a
transmission slot level, so as to perform code
multiplexing.
In this case, radio resources to which any
of the common control channel and the control
signaling channel is not assigned are assigned
another physical channel such as an after-mentioned
shared channel for example.

-34-
Accordingly, by using a plurality of
frequency blocks to perform code-multiplexing for
the common control channel and the control signaling
channel, receiving quality can be improved due to
frequency diversity effect.
Next, assignment of radio resources for
the shared channel is described.
Since the shared channel is information
directed to each user, packet scheduling can be
applied. As to the frequency axis direction, the
radio resource assignment unit 140 divides the
entire frequency band assigned to the system in
units of one sub-carrier or a plurality of sub-
carriers, as to the time axis direction, the radio
resource assignment unit 140 divides in units of one
or a plurality of OFDM symbols, and divides the code
axis direction in units of one or a plurality of
codes, so that each frequency block is configured by
one or a plurality sub-carries, one or a plurality
of OFDM symbols, and one or a plurality of codes,
and radio resources are assigned in units of the
frequency block.
In addition, the radio resource assignment
unit 140 performs packet scheduling for the time
domain and the frequency domain to select at least
one frequency block from among a plurality of
frequency blocks. The result of packet scheduling
is reported to a receiving station.
In addition, the radio resource assignment
unit 140 assigns optimum frequency blocks based on
feedback information, from the receiving station,
that is a receiving channel status for example, that
is a receiving SIR, for example.
Accordingly, frequency blocks to be
assigned to each user can be dynamically changed, so
that frequency blocks corresponding to good channel
status can be assigned. Accordingly, receiving

-35-
characteristics in the receiver can be improved due
to a multi-user diversity effect.
As an example, a case where the number of
users is eight is described with reference to Fig.14.
That is, a case is described where shared channels
for the eight users are assigned to radio resources.
The radio resource assignment unit 140
divides the entire frequency band assigned to the
system into eight, for example, to form frequency
blocks, and perform radio resource assignment for
each transmission slot according to receiving status
of each user. Here, the frequency block is a radio
resource assignment unit formed when dividing the
system band into a plurality of bands in each
transmission slot.
In addition, for example, when information
amounts to be transmitted for each user are
different, the radio resource assignment unit 140
may assign the frequency block according to a data
rate. For example, the frequency block is assigned
according to a signal of a high data rate that is,
for example, download of a large sized file, and a
signal of a low transmission rate such as voice. In
this case, in the case of the high data rate, "size
of a packet desired to be transmitted" becomes
larger than the size of the frequency block. In the
case of the low data rate, "size of a packet desired
to be transmitted" becomes smaller than the size of
the frequency block.
A case where radio resources are assigned
to a user of the high data rate is described with
reference to Fig.15.
In the case of the high data rate, since
"size of a packet desired to be transmitted" is
larger than the size of the frequency block, the
radio resource assignment unit 140 assigns a
plurality of frequency blocks (chunks) in a

-36-
transmission slot. For example, for a user #1 of
the high data rate, three frequency blocks are
assigned in a transmission slot, and four frequency
blocks are assigned in another transmission slot.
Next, a case where radio resources are
assigned to a user of the low data rate is described
with reference to Fig.16.
In the case of the low data rate, since
"size of a packet desired to be transmitted" is
smaller than the size of the frequency block, the
radio resource assignment unit 140 assigns a batch
of users of low data rate to one frequency block.
For the user of the low data rate, since the "size
of a packet desired to be transmitted" is smaller
than the size of the frequency block, one block
cannot be filled with information to be transmitted.
However, it wastes radio resources to use only a
part of the frequency block and keep remaining part
empty for performing transmission.
Therefore, a plurality of users of the low
speed data rate are assigned one frequency block.
For example, the radio resource assignment unit 140
assigns users #9 and #10 of the low data rate to a
same frequency block to transmit it by multiplexing
the users. Accordingly, receiving quality can be
improved due to multi-user diversity.
In addition, when assigning radio
resources to users of the low data rate, the radio
resource assignment unit 140 may assign the
resources across at least two frequency blocks in a
plurality of frequency blocks included in a same
transmission slot. When users of the low data rate
are assigned to one frequency block as a whole,
there is a case where the multi-user diversity
effect is deteriorated since a set of users of good
receiving status is not necessarily assigned.
In such a case, radio resources are

-37-
assigned across a plurality of frequency blocks.
For example, as shown in Fig.l7A, each of users #9,
#10, #11 and #12 of the low data rate is assigned
across at least two frequency blocks of frequency
blocks included in a same transmission slot.
Accordingly, frequency diversity effect can be
obtained, and receiving quality in the receiver can
be improved.
Although radio resource assignment to
shared channels for users of low data rate is
described in Fig.l7A, a similar radio resource
assignment method is effective when performing
assignment for users moving at high speed or users
where receiving status is extremely bad. This is
because, since speed of channel variation becomes
very high for the users moving at high speed, radio
resource assignment by packet scheduling cannot
follow the variation so that improvement effect due
to multi-user diversity cannot be obtained. In
addition, as to the users where the receiving status
is extremely bad, since the data rate becomes very
low, enough channel coding gain cannot be obtained
only by assigning a part of a particular frequency
block, so that there may be a case where the
characteristics are deteriorated. The user in the
above-mentioned conditions, as shown in Fig.l7B, is
assigned resources across at least two frequency
blocks of frequency blocks included in a same
transmission slot. Accordingly, frequency diversity
effect can be obtained so that receiving quality in
the receiver can be improved.
Next, a case where radio resources are
assigned to a multicast channel is described with
reference to Fig.18. In the case of multicast, data
is transmitted from a plurality of transmitters to a
particular user.
As shown in the configuration example 1,

-38-
when assigning radio resources to a multicast
channel, the radio resource assignment unit 140
assigns the multicast channel to at least a part of
symbols forming a transmission slot that indicates a
unit (TTI: Transmission Time Interval) of
transmission in packet transmission.
Also, in this case, when assigning radio
resources to a physical channel other than the
multicast channel, the radio resource assignment
unit 140 assigns a symbol other than symbols to
which the multicast channel is assigned.
Accordingly, since the multicast channel can be
mapped over the entire frequency band, receiving
quality in the receiver can be improved due to
frequency diversity effect.
As shown in the configuration example 2,
when assigning radio resources to a multicast
channel, the radio resource assignment unit 140 may
assign the multicast channel to at least a part of
symbols forming a transmission slot that indicates a
unit (TTI: Transmission Time Interval) of
transmission in packet transmission, and may perform
assignment so as to transmit a same transmission
slot a plurality of times, for example, two times,
using a plurality of transmission slots.
Also, in this case, when assigning radio
resources to a physical channel other than the
multicast channel, the radio resource assignment
unit 140 assigns a symbol other than symbols to
which the multicast channel is assigned.
Accordingly, since the multicast channel can be
mapped over the entire frequency band, receiving
quality in the receiver can be improved due to
frequency diversity effect. In addition, effect of
time diversity can be also obtained.
In addition, in the configuration example
2, in the multicast channel transmitted secondly or

-39-
later, information that is the same as one
transmitted first is transmitted. In this case,
demodulation processing is performed in the receiver
side so that it is determined whether there is an
demodulation error. When there is no demodulation
error, control is performed so as not to receive a
multicast channel that is transmitted secondly or
later. For example, in many cases, a user located
near a transmitter can receive information at the
first try. By controlling so as not to receive a
multicast channel that is transmitted secondly or
later, consumption of a battery can be suppressed.
When there is a demodulation error, the
information is discarded and the multicast channel
transmitted secondly or later is demodulated again.
In addition, when there is a demodulation error, the
information may not be discarded so as to perform
packet combining for the multicast channel
transmitted secondly or later and the multicast
channel received previously to perform demodulation
again. Accordingly, receiving SIR can be improved.
In addition, in the configuration example
2, the multicast channel transmitted secondly or
later may be for transmitting information different
from one in the first transition. For example, the
multicast channel transmitted secondly or later may
be configured to transmit a packet on which
puncturing is performed with a pattern different
from a pattern used in the first transmission. In
this case, demodulation processing is performed in
the receiver side, and it is determined whether
there is a demodulation error. When there is no
demodulation error, the receiver is controlled such
that it does not receive a multicast channel
transmitted secondly or later. For example, in many
cases, a user located near a transmitter can receive
information at the first try. By controlling the

-40-
user so as not to receive a multicast channel that
is transmitted secondly or later, consumption of a
battery can be suppressed.
When there is a demodulation error, the
information may not be discarded, and packet
combining may be performed between the multicast
channel transmitted secondly or later and the
multicast channel received previously to perform
demodulation again. Accordingly, coding gain can be
improved.
In addition, in the configuration example
2, the multicast channel transmitted secondly or
later may be configured to transmit information
different from one sent in the first transmission.
For example, information indicating the multicast
channel may be divided into two or more. When
information is stored in the multicast channel
transmitted for the first time and redundancy code
is stored in the multicast channel transmitted
secondly or later, the multicast channel transmitted
secondly or later cannot be decoded when receiving
of the multicast channel transmitted first is failed,
In such a case, by dividing information
indicating the multicast channel into two or more
for transmission, receiving quality in the receiver
can be improved due to time diversity effect. In
this case, a transmission slot for transmitting
information indicating the multicast channel by
dividing it and a packet storing the redundancy code
may be transmitted.
In this case, it is necessary to determine
a number of division of the multicast channel
beforehand in the transmitter and the receiver. As
information to be determined beforehand, a packet
number for performing packet combining, a puncture
pattern, constellation, and a bit indicating new or
retransmission packet are necessary. The bit

-41-
indicating a new or retransmitted packet is
necessary for avoiding incorrect combining
considering ACK/NACK bit error.
Next, a method for assigning radio
resources for a shared channel in a frequency block
is described. The radio resource assignment unit
140 multiplexes shared channels in a frequency block
to which the radio resources are assigned.
First, a method is described for assigning
radio resources to a user of high data rate.
For example, for a user of the high speed
data rate, the radio resource assignment unit 140
multiplexes signals of one user within the frequency
block based on the result of frequency/time
scheduling. For example, as shown in Fig.19, the
radio resource assignment unit 140 combines time
multiplexing and frequency multiplexing to multiplex
signals of one user.
Next, a method for assigning radio
resources to users of low data rate is described
with reference to Fig.20.
For example, for the user of low data rate,
the radio resource assignment unit 140 time-
multiplexes signals of a plurality of users within a
frequency block based on the result of
frequency/time scheduling. Accordingly, receiving
quality can be improved due to frequency diversity
effect.
In addition, for example, for the user of
the low data rate, the radio resource assignment
unit 140 may frequency-multiplex signals of a
plurality of users within a frequency block based on
the result of frequency/time scheduling.
Accordingly, receiving quality can be improved due
to time diversity effect.
In addition, for example, for the user of
the low data rate, the radio resource assignment

-42-
unit 140 may code-multiplex signals of a plurality
of users within a frequency block based on the
result of frequency/time scheduling. Accordingly,
compared to time multiplexing and frequency
multiplexing, time diversity effect and frequency
diversity effect can be. obtained so that receiving
quality can be improved. In addition, by applying a
low speed data modulation scheme such as QPSK and
BPSK for example, effect of inter-code interference
caused by collapse of orthogonally can be decreased.
In addition, for example, for the user of
the low data rate, the radio resource assignment
unit 140 may multiplex signals of a plurality of
users within the frequency block by combining time
multiplexing, frequency multiplexing and code
multiplexing based on the result of frequency/time
scheduling.
Detailed descriptions are given.
As mentioned above, as shown in Fig.21,
the radio resource assignment unit 140, for users of
the low data rate, time-multiplexes signals of users
within the frequency block. Accordingly, especially
in an environment where there are many users of low
speed mobility, receiving quality can be improved by
the frequency diversity effect.
On the other hand, as shown in Fig.22A,
the radio resource assignment unit 140, for users of
the high data rate, multiplexes signals of users
within the frequency block by combining time
multiplexing and frequency multiplexing.
In addition, as shown in Fig.22B, the
radio resource assignment unit 140, for users of the
high data rate, may multiplex signals of users
within the frequency block by combining time
multiplexing and code multiplexing.
In addition, the radio resource assignment
unit 140, further for users of the low data rate,

-43-
may multiplex signals of users within the frequency
block by combining time multiplexing, frequency
multiplexing and code multiplexing.
For example, as shown in Figs.23A and 23B,
the radio resource assignment unit 140 multiplexes
signals of a plurality of users within the frequency
block in the time domain/the frequency domain.
Fig.23A corresponds to a case where continuous time
domains are assigned, and Fig.23B corresponds to a
case where discrete time domains are assigned.
In addition, for example, as shown in
Fig.24, the radio resource assignment unit 140 may
randomly select blocks formed by sub-carriers and
OFDM symbols in time domain/frequency domain to
multiplex signals of a plurality of users in the
frequency block.
In addition, for example, as shown in
Figs.25A and 25B, the radio resource assignment unit
140 may multiplex signals of a plurality of users in
the frequency block in time domain/code domain.
Fig.25A corresponds to a case where consecutive
frequency domains are assigned (Hybrid TDM/CDM), and
Fig.25B corresponds to a case where discrete
frequency domains are assigned (Hybrid TDM/CDM).
In addition, for example, as shown in
Figs.26A and 26B, the radio resource assignment unit
140 may multiplex signals of a plurality of users in
the frequency block in frequency domain/code domain.
Fig.26A corresponds to a case where consecutive time
domains are assigned (Hybrid FDM/CDM), and Fig.26B
corresponds to a case where discrete time domains
are assigned (Hybrid FDM/CDM).
In addition, for example, as shown in
Figs.27A and 27B, the radio resource assignment unit
140 may multiplex signals of a plurality of users in
the frequency block in time domain/frequency
domain/code domain. Fig.27A corresponds to a case

-44-
where consecutive frequency domains are assigned
(Hybrid TDM/FDM/CDM), and Fig.27B corresponds to a
case where discrete frequency domains are assigned
(Hybrid TDM/FDM/CDM).
As mentioned above, by dividing the time
domain/frequency domain/code domain in the frequency
block and assigning a signal of a user to each
divided region, multiplexing among a plurality of
users in the frequency block can be performed.
Next, operation of the transmission
apparatus 100 of the present invention is described
with reference to Fig.28.
Information to be transmitted by a common
control channel is supplied to the channel coding
unit 102. In the channel coding unit 102, channel
coding is performed on the supplied information
according to a preset channel coding rate (step
S2702).
Next, in data modulation unit 104, data
modulation is performed on information, on which
channel coding has been performed, according to a
preset data modulation scheme (step S2704) .
Next, the spreading unit 106 spreads
information on which data modulation has been
performed according to a preset spreading rate (step
S2706).
On the other hand, the packet scheduling
unit 128 selects users and determines a data
modulation scheme and a coding rate used for each
selected user according to supplied transmission
information to each user and receiving quality of
each user (step S2708).
Next, in channel coding unit 122, channel
coding is performed on information to be transmitted
to each user according to the coding rate determined
by the packet scheduling unit 128 (step S2710) .
Next, in the data modulation unit 104,

-45-
data modulation is performed on information, to be
transmitted to each user, on which channel coding
has been performed, according to the data modulation
scheme determined by the packet scheduling unit 128
(step S2712).
Next, the spreading unit 106 spreads
information, to be transmitted to each user, on
which data modulation has been performed, according
to the spreading factor determined by the packet
scheduling unit 128 (step S2714).
In addition, the packet scheduling unit
128 supplies information of the selected user and
information such as selected data modulation scheme
and coding rate etc. to the channel coding unit 112.
In the channel coding unit 112, channel
coding is performed on supplied information
according to a preset channel coding rate (step
S2716).
Next, in the data modulation unit 104,
data modulation is performed on the information on
which channel coding has been performed according to
a preset data modulation scheme (step S2718) .
Next, the spreading unit 106 spreads
information on which data modulation has been
performed according to a preset spreading factor
(step S2720).
Next, based on input information (decision
criteria) used for assignment such as a channel type,
a data rate, and mobility, etc., the radio resource
assignment unit 140 assigns, to radio resources,
information to be transmitted by the common control
channel, information of selected users, information
such as the selected data modulation scheme and the
coding rate, and information to be transmitted to
each user (step S2722) .
Next, an OFDM signal is generated and
transmitted (step S2724) .

-46-
The present international application
claims priority based on Japanese patent application
No.2005-105493, filed in the JPO on March 31, 2005,
and priority based on Japanese patent application
No.2005-174403, filed in the JPO on June 14, 2005,
and the entire contents of the applications of
No.2005-105493 and No.2005-174403 are incorporated
herein by reference.
[Industrial Applicability]
The transmission apparatus and the radio
resource assignment method of the present invention
can be applied to a mobile communication system.

-47-
CLAIMS
1. A transmission apparatus for
transmitting a plurality of sub-carriers comprising:
radio resource assignment means that
assigns radio resources to each physical channel
according to a type of the physical channel; and
transmission means that transmits
information to be transmitted by each physical
channel using the assigned radio resources.
2. The transmission apparatus as claimed
in claim 1, further comprising:
scheduling means that selects a user for
transmission based on information indicating
receiving quality from each user.
3. The transmission apparatus as claimed
in claim 1, wherein the radio resource assignment
means assigns at least one sub-carrier block of a
plurality of sub-carrier blocks divided from an
entire frequency band that is assigned to the own
system to at least one of a common control channel
and a channel for transmitting control information
indicating a selected user.
4. The transmission apparatus as claimed
in claim 1, wherein the radio resource assignment

-48-
means assigns radio resources to at least one of a
common control channel and a channel for
transmitting control information indicating a
selected user based on frequency blocks formed by a
plurality of sub-carriers divided from an entire
frequency band assigned to the own system and a
plurality of symbols.
5. The transmission apparatus as claimed
in claim 4, wherein the radio resource assignment
means assigns at least a part of symbols forming the
frequency blocks to at least one of the common
control channel and the channel for transmitting the
control information.
6. The transmission apparatus as claimed
in claim 5, wherein the radio resource assignment
means assigns a predetermined symbol in the
frequency blocks included in the transmission slot
to at least one of the common control channel and
the channel for transmitting the control information
indicating the selected user.
7. The transmission apparatus as claimed
in claim 6, wherein the radio resource assignment
means performs assignment for at least one of the
common control channel and the channel for
transmitting the control information indicating the

-49-
selected user such that positions of predetermined
symbols of the frequency blocks included in the
transmission slot are different in at least a part
of sub-carrier blocks.
8. The transmission apparatus as claimed
in claim 7, wherein the radio resource assignment
means assigns the channel for transmitting the
control information to a plurality of transmission
slots.
9. The transmission apparatus as claimed
in claim 8, wherein the radio resource assignment
means assigns the channel for transmitting the
control information to a symbol position different
from that in a transmission slot that is previously
sent.

10. The transmission apparatus as claimed
in claim 8, wherein the radio resource assignment
means assigns, to a plurality of transmission slots,
the channel for transmitting the control information
that is divided .
11. The transmission apparatus as claimed

-50-
in claim 1, wherein the radio resource assignment
means assigns a predetermined symbol in a
transmission slot to a multicast channel.
12. The transmission apparatus as claimed
in claim 11, wherein the radio resource assignment
means assigns a channel for the multicast channel to
a plurality of transmission slots.
13. The transmission apparatus as claimed
in claim 12, wherein the radio resource assignment
means assigns the channel for transmitting the
multicast to a symbol position different from that
in a transmission slot that is previously sent.
14. The transmission apparatus as claimed
in claim 12, wherein the radio resource assignment
means assigns the channel for transmitting divided
data to be transmitted by the multicast to a
plurality of transmission slots.
15. The transmission apparatus as claimed
in claim 2, wherein the scheduling means performs
packet scheduling in a time domain and a frequency
domain, and determines, as a frequency block to be

-51-
assigned to a shared channel, at least one of
frequency blocks formed by a plurality of sub-
carriers divided from an entire frequency band
assigned to the own system and a plurality of
symbols.
16. The transmission apparatus as claimed
in claim 2, wherein the scheduling means determines
a radio parameter used for transmission to the
selected user.
17. The transmission apparatus as claimed
in claim 15, wherein the radio resource assignment
means assigns radio resources in the frequency block
to signals transmitted to a plurality of users based
on the frequency block, formed by one or a plurality
of sub-carriers, one or a plurality of symbols and
one or a plurality of codes, in which an entire
frequency band assigned to the system is divided in
units of one or a plurality of sub-carriers in the
frequency axis direction, the time axis direction is
divided in units of one or a plurality of symbols,
and the code axis direction is divided in units of
one or a plurality of codes.
18. The transmission apparatus as claimed
in claim 15, wherein the radio resource assignment
means assigns the frequency block based on at least

-52-
one of data rate and mobility.
19. The transmission apparatus as claimed
in claim 16, wherein the radio resource assignment
means performs assignment to a plurality of
frequency blocks included in the transmission slot
based on the data rate.
20. The transmission apparatus as claimed
in claim 18, wherein the radio resource assignment
means assigns signals transmitted to a plurality of
users to one frequency block based on the data rate.
21. The transmission apparatus as claimed
in claim 20, wherein the radio resource assignment
means performs assignment to a plurality of
frequency blocks included in the transmission slot.
22. A radio resource assignment method in
a transmission apparatus for transmitting a
plurality of sub-carriers comprising:
a step of receiving information indicating
receiving quality;
a step of determining a user for
transmission based on the receiving quality;

-53-
a step of assigning radio resources to
each physical channel according to a type of the
physical channel; and
a step of transmitting information to be
transmitted by each physical channel using the
assigned radio resources to the user.
23. The radio resource assignment method
as claimed in claim 22, wherein the step of
assigning the radio resources includes a step of
assigning, to at least one of a common control
channel and a channel for transmitting control
information indicating a selected user, at least one
sub-carrier block of a plurality of sub-carrier
blocks divided from an entire frequency band
assigned to the own system.
24. The radio resource assignment method
as claimed in claim 23, wherein the step of
assigning the radio resources includes a step of
assigning radio resources to at least one of the
common control channel and the channel for
transmitting control information indicating a
selected user based on frequency blocks formed by a
plurality of sub-carriers divided from an entire
frequency band assigned to the own system and a
plurality of symbols.

-54-
25. The radio resource assignment method
as claimed in claim 23, wherein the step of
assigning the radio resources includes a step of
performing assignment for at least one of the common
control channel and the channel for transmitting the
control information indicating the selected user
such that positions of predetermined symbols of the
frequency blocks included in the transmission slot
are different in at least a part of sub-carrier
blocks.
26. The radio resource assignment method
as claimed in claim 25, wherein the step of
assigning the radio resources includes a step of
assigning the channel for transmitting the control
information to a plurality of transmission slots.
27. The radio resource assignment method
as claimed in claim 22, comprising:
a step of performing packet scheduling in
a time domain and a frequency domain; and
a step of determining a frequency block to
be assigned to a shared channel from among frequency
blocks formed by a plurality of sub-carriers divided
from an entire frequency band assigned to the own
system and a plurality of symbols.

-55-
28. The radio resource assignment method
as claimed in claim 27, wherein the radio resource
assignment step assigns radio resources in the
frequency block to signals transmitted to a
plurality of users based on the frequency block,
formed by one or a plurality of sub-carriers, one or
a plurality of symbols and one or a plurality of
codes, in which an entire frequency band assigned to
the system is divided in units of one or a plurality
of sub-carriers in the frequency axis direction, the
time axis direction is divided in units of one or a
plurality of symbols, and the code axis direction is
divided in units of one or a plurality of codes.
29. The radio resource assignment method
as claimed in claim 22, comprising assigning a
predetermined symbol in a transmission slot to a
multicast channel.

A transmission apparatus is provided with
radio resource assignment means that assigns radio
resources to each physical channel according to a
type of the physical channel; and transmission means
that transmits information to be transmitted by each
physical channel using the assigned radio resources.

Documents:

03594-kolnp-2007-abstract.pdf

03594-kolnp-2007-claims.pdf

03594-kolnp-2007-correspondence others.pdf

03594-kolnp-2007-description complete.pdf

03594-kolnp-2007-drawings.pdf

03594-kolnp-2007-form 1.pdf

03594-kolnp-2007-form 3.pdf

03594-kolnp-2007-form 5.pdf

03594-kolnp-2007-international publication.pdf

03594-kolnp-2007-international search report.pdf

03594-kolnp-2007-pa.pdf

03594-kolnp-2007-pct priority document notification.pdf

03594-kolnp-2007-pct request form.pdf

3594-KOLNP-2007-(07-01-2015)-ANNEXURE TO FORM 3.pdf

3594-KOLNP-2007-(07-01-2015)-CORRESPONDENCE.pdf

3594-KOLNP-2007-(28-07-2014)-ABSTRACT.pdf

3594-KOLNP-2007-(28-07-2014)-ANNEXURE TO FORM 3.pdf

3594-KOLNP-2007-(28-07-2014)-CLAIMS.pdf

3594-KOLNP-2007-(28-07-2014)-CORRESPONDENCE.pdf

3594-KOLNP-2007-(28-07-2014)-DRAWINGS.pdf

3594-KOLNP-2007-(28-07-2014)-FORM-2.pdf

3594-KOLNP-2007-(28-07-2014)-FORM-3.pdf

3594-KOLNP-2007-(28-07-2014)-FORM-5.pdf

3594-KOLNP-2007-(28-07-2014)-OTHER.2.pdf

3594-KOLNP-2007-(28-07-2014)-OTHER.3.pdf

3594-KOLNP-2007-(28-07-2014)-OTHERS.1.pdf

3594-KOLNP-2007-(28-07-2014)-OTHERS.pdf

3594-KOLNP-2007-(28-07-2014)-PA.pdf

3594-KOLNP-2007-(28-07-2014)-PETITION UNDER RULE 137.pdf

3594-KOLNP-2007-ASSIGNMENT.pdf

3594-KOLNP-2007-CLAIMS 1.1.pdf

3594-KOLNP-2007-CORRESPONDENCE OTHERS 1.1.pdf

3594-KOLNP-2007-CORRESPONDENCE.pdf

3594-KOLNP-2007-FORM 13.pdf

3594-kolnp-2007-form 18.pdf

3594-KOLNP-2007-FORM 3-1.1.pdf

abstract-03594-kolnp-2007.jpg


Patent Number 265753
Indian Patent Application Number 3594/KOLNP/2007
PG Journal Number 11/2015
Publication Date 13-Mar-2015
Grant Date 12-Mar-2015
Date of Filing 24-Sep-2007
Name of Patentee NTT DOCOMO INC
Applicant Address 11-1 NAGATACHO 2-CHOME CHIYODA-KU, TOKYO
Inventors:
# Inventor's Name Inventor's Address
1 MIKI NOBUHIKO C/O INTELLECTUAL PROPERTY DEPARTMENT, NTT DOCOMO, INC. SANNO PARK TOWER, 11-1 NAGATACHO 2-CHOME,, CHIYODA-KU, TOKYO 100-6150
2 HIGUCHI KENICHI C/O INTELLECTUAL PROPERTY DEPARTMENT, NTT DOCOMO, INC. SANNO PARK TOWER, 11-1 NAGATACHO 2-CHOME,, CHIYODA-KU, TOKYO 100-6150
3 SAWAHASHI MAMORU C/O INTELLECTUAL PROPERTY DEPARTMENT, NTT DOCOMO, INC. SANNO PARK TOWER, 11-1 NAGATACHO 2-CHOME,, CHIYODA-KU, TOKYO 100-6150
4 ATARASHI HIROYUKI C/O INTELLECTUAL PROPERTY DEPARTMENT, NTT DOCOMO, INC. SANNO PARK TOWER, 11-1 NAGATACHO 2-CHOME,, CHIYODA-KU, TOKYO 100-6150
5 TANNO MOTOHIRO C/O INTELLECTUAL PROPERTY DEPARTMENT, NTT DOCOMO, INC. SANNO PARK TOWER, 11-1 NAGATACHO 2-CHOME,, CHIYODA-KU, TOKYO 100-6150
PCT International Classification Number H04Q 7/36, H04B 1/69
PCT International Application Number PCT/JP2006/305518
PCT International Filing date 2006-03-20
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2005-105493 2005-03-31 Japan
2 2005-174403 2005-06-14 Japan