U.S. patent number 9,271,268 [Application Number 13/520,865] was granted by the patent office on 2016-02-23 for wireless transmission device, wireless reception device, and bandwidth allocation method for setting a band where other bands indicated by continuous band allocation information do not overlap.
This patent grant is currently assigned to PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA. The grantee listed for this patent is Masaru Fukuoka, Daichi Imamura, Takashi Iwai, Seigo Nakao, Akihiko Nishio, Yoshihiko Ogawa, Shozo Okasaka. Invention is credited to Masaru Fukuoka, Daichi Imamura, Takashi Iwai, Seigo Nakao, Akihiko Nishio, Yoshihiko Ogawa, Shozo Okasaka.
United States Patent |
9,271,268 |
Iwai , et al. |
February 23, 2016 |
Wireless transmission device, wireless reception device, and
bandwidth allocation method for setting a band where other bands
indicated by continuous band allocation information do not
overlap
Abstract
Provided are a wireless transmission device, a wireless
reception device, and a bandwidth allocation method for, when
non-contiguous bands allocation is performed, improving the
frequency resource use efficiency of a system and thereby improving
the system performance. RIV decoding unit (106) decodes start RBG#
and end RBG# that are indicated by each RIV output from scheduling
information decoding unit (104). Allocation boundary setting unit
(107) previously adds a predetermined offset to the boundary of
each RIV so that the boundaries of the allocations of respective
RIVs are different from each other. Based on the start RBG# and end
RBG# output from RIV decoding unit (106) and the boundaries of the
allocations of respective RIVs output from allocation boundary
setting unit (107), transmission bandwidth determination unit (108)
determines, as allocated bandwidths, the bandwidths that are
indicated by a plurality of RIVs and are not overlapped with each
other.
Inventors: |
Iwai; Takashi (Ishikawa,
JP), Nishio; Akihiko (Kanagawa, JP),
Imamura; Daichi (Kanagawa, JP), Nakao; Seigo
(Kanagawa, JP), Ogawa; Yoshihiko (Kanagawa,
JP), Okasaka; Shozo (Kanagawa, JP),
Fukuoka; Masaru (Ishikawa, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Iwai; Takashi
Nishio; Akihiko
Imamura; Daichi
Nakao; Seigo
Ogawa; Yoshihiko
Okasaka; Shozo
Fukuoka; Masaru |
Ishikawa
Kanagawa
Kanagawa
Kanagawa
Kanagawa
Kanagawa
Ishikawa |
N/A
N/A
N/A
N/A
N/A
N/A
N/A |
JP
JP
JP
JP
JP
JP
JP |
|
|
Assignee: |
PANASONIC INTELLECTUAL PROPERTY
CORPORATION OF AMERICA (Torrance, CA)
|
Family
ID: |
44305505 |
Appl.
No.: |
13/520,865 |
Filed: |
January 7, 2011 |
PCT
Filed: |
January 07, 2011 |
PCT No.: |
PCT/JP2011/000043 |
371(c)(1),(2),(4) Date: |
July 06, 2012 |
PCT
Pub. No.: |
WO2011/083769 |
PCT
Pub. Date: |
July 14, 2011 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20130072242 A1 |
Mar 21, 2013 |
|
Foreign Application Priority Data
|
|
|
|
|
Jan 8, 2010 [JP] |
|
|
2010-003154 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L
5/0041 (20130101); H04L 5/0037 (20130101); H04L
5/0091 (20130101); H04L 5/0067 (20130101); H04W
72/0406 (20130101); H04W 72/0453 (20130101) |
Current International
Class: |
H04W
72/04 (20090101); H04L 5/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
ZTE, Uplink Non-contiguous Resource Allocation for LTE-Advanced,
Nov. 13, 2009, 3GPP TSG RAN WG1 Meeting #59 R1-095010, pp. 1-7.
cited by examiner .
International Search Report dated Feb. 8, 2011. cited by applicant
.
3GPP TSG RAN WG1 #58, "Control Signaling for Non-Contiguous UL
Resource Allocations," R1-093391, Aug. 24-28, 2009, pp. 1-6, p. 3,
Line 13. cited by applicant .
3GPP TSG-RAN WG1 #59bis, "On the non-contiguous UL resource
allocation," R1-100664, Jan. 18-22, 2010, pp. 1-5. cited by
applicant .
3PP TSG-RAN WG1 Meeting #59bis, "Signaling for UL non-contiguous
resource allocation," R1-100370, Jan. 18-22, 2010, pp. 1-5. cited
by applicant .
3GPP TSG RAN WG1 Meeting #55bis, "System performance of uplink
non-contiguous resource allocation," R1-090257, Jan. 12-16, 2009,
pp. 1-7, p. 3, Line 10. cited by applicant.
|
Primary Examiner: Rivero; Alejandro
Attorney, Agent or Firm: Dickinson Wright PLLC
Claims
The invention claimed is:
1. A radio transmission apparatus comprising: a receiver configured
to receive a plurality of allocation information, each of the
plurality of allocation information indicating allocation of
continuous bands each comprised of continuous resource blocks
divided into at least one resource block group, the continuous
bands including an overlapping portion; a transmission band setting
unit configured to set a transmission band based on the plurality
of allocation information, the transmission band being a band
including the entirety of the continuous bands except the
overlapping portion between said continuous bands indicated by the
plurality of allocation information, respectively; and a
transmitter configured to transmit transmission data on the set
transmission band, wherein boundaries for dividing resource blocks
into resource block groups differ between the plurality of
allocation information.
2. The radio transmission apparatus according to claim 1, wherein
the transmission band setting unit sets, as the transmission band,
a number of clusters less than a number of allocation information
using allocation information indicating allocation of a band beyond
one end of a system band.
3. The radio transmission apparatus according to claim 1, wherein
the transmission band setting unit sets the transmission bandbased
on offset information indicating whether or not the boundaries are
different.
4. The radio transmission apparatus according to claim 3, wherein
information to indicate whether or not continuous bands indicated
by the plurality of allocation information overlap is used as the
offset information.
5. The radio transmission apparatus according to claim 4, wherein
the boundaries are different when the continuous bands overlap, and
the boundaries are the same when the continuous bands do not
overlap.
6. The radio transmission apparatus according to claim 1, wherein,
when an allocation bandwidth indicatable by the allocation
information is limited to equal to or less than a system bandwidth,
a band not indicatable by the allocation information is set to a
central area of a system band, and continuous bands indicated by
each of the allocation information are cyclically shifted in the
system band.
7. A radio reception apparatus comprising: a band setting unit
configured to set a transmission band, the transmission band being
a band including the entirety of continuous bands except an
overlapping portion that exists between the continuous bands, which
are indicated by a plurality of allocation information,
respectively, each of the continuous bands being comprised of
continuous resource blocks divided into at least one resource block
group; a transmitter configured to transmit the plurality of
allocation information to a communication counterpart; and a
receiver configured to receive signals, which are transmitted from
the communication counterpart on the transmission band based on the
plurality of allocation information, wherein boundaries for
dividing resource blocks into resource block groups differ between
the plurality of allocation information.
8. A band allocation method performed by a radio communication
apparatus comprising: setting a transmission band, the transmission
band being a band including the entirety of continuous bands except
an overlapping portion that exists between the continuous bands,
which are indicated by a plurality of allocation information,
respectively, and which are comprised of continuous resource blocks
divided into resource block groups; transmitting the plurality of
allocation information to a communication counterpart; and
receiving signals, which are transmitted from the communication
counterpart on the transmission band based on the plurality of
allocation information, wherein boundaries for dividing resource
blocks into resource block groups differ between the plurality of
allocation information.
Description
TECHNICAL FIELD
The present invention relates to a radio transmission apparatus, a
radio reception apparatus, and a band allocation method that
allocate non-contiguous bands.
BACKGROUND ART
The upstream channel of 3GPP LTE (3rd Generation Partnership
Project Long Term Evolution) employs contiguous band transmission
in which a data signal of each terminal is allocated to contiguous
frequency band to reduce CM/PAPR (Cubic Metric/Peak to Average
Power Ratio). Each terminal transmits data according to frequency
allocation resource information notified from a base station. The
frequency allocation resource information means two pieces of
information that include a start RB (Resource Block) number and an
end RB number where the term "RB" indicates a frequency allocation
unit formed of twelve subcarriers.
In an LTE network, the base station notifies the terminals of the
frequency allocation resource information using information
referred to herein as RIV (Resource Indication Value). RIV
indicates the allocation resource information with a tree structure
as shown in FIG. 1. FIG. 1 shows the RIV tree structure that
indicates contiguous band allocation within RB#0 to RB#5. When the
base station designates RIV=6, for example, the allocation resource
information for the terminal includes RB#0 and RB#1 that are the
base of the tree. Similarly, when the base station designates
RIV=14, allocation resource information for the terminal includes
RB#2 to RB#4 that are the base of the tree. RB#0 to RB#5 located at
the base of the tree correspond to RIVs=0 to 5, respectively.
Assuming that RIVs=0 to 5 at the base of the tree are the first
step, RIVs=6 to 10, RIVs=12 to 15, RIVs=18 to 20, RIVs=17 to 16,
and RIV=11 correspond to the second, third, fourth, fifth, and
sixth steps, respectively. Utilization of the first to sixth RIVs
enables the contiguous band with twenty-one patterns to be
indicated out of RB#0 to RB#5 located at the base of the tree.
It is studied that the upstream channel of LIE-Advanced as an
evolved form of LTE employs non-contiguous band transmission in
addition to the contiguous band transmission to improve sector
throughput performance (see Non-Patent Literature 1).
The non-contiguous band transmission is a transmission method of
allocating data signals and reference signals to non-contiguous
bands that are distributed over a wide band. The non-contiguous
band transmission can allocate the data signals and the reference
signals to discrete frequency bands as shown in FIG. 2. Thus, the
non-contiguous band transmission can increase the degree of freedom
of frequency band allocation of the data signal and the reference
signal at each terminal to have a larger frequency scheduling
effect compared to the contiguous band transmission.
A conventional method of sending the non-contiguous band allocation
resource information from the base station to the terminals is to
notify any terminal of the non-contiguous band allocation by
sending a plurality of RIVs (contiguous band allocation
information) to the terminal (see Non-Patent Literature 2).
As shown in FIG. 3, NPL 2 discloses that RBG numbers (RBG#) are
assigned by allocation granularity (4 RB in FIG. 3) referred to
herein as RBG (Resource Block Group) and the scheduled terminal is
notified of RIV indicating a start RBG# and an end RBG#. The base
station notifies the terminal of two RIVs (RIV#1 and RIV #2) as
shown in FIG. 3, thereby enabling allocation of two clusters (each
being a contiguous band block), i.e., non-contiguous bands to the
terminal. Thus, specifying RBG by taking advantage of RIVs
themselves used in conventional LTE enables non-contiguous band
allocation to be easily introduced into LTE-Advanced.
An RBG size is determined according to a system bandwidth as shown
in FIG. 4. For the system bandwidth of 20 MHz, for example, the RBG
size will be 4 RB as shown in FIG. 3. The number of signaling bits
of the allocation resource information is thus reduced by
increasing RBG size according to the magnitude of the system
bandwidth.
CITATION LIST
Non-Patent Literature
NPL 1
R1-090257, Panasonic, "System performance of uplink non-contiguous
resource allocation" NPL 2 R1-093391, Samsung, "Control Signaling
for Non-Contiguous UL Resource Allocations"
SUMMARY OF INVENTION
Technical Problem
However, the conventional non-contiguous band allocation method
using a plurality of RIVs decreases the usage efficiency of system
frequency resources to impair system performance due to coarse
allocation granularity.
In the upstream channel of LTE, for example, control signals
(PUCCHs) with the bandwidth of 1 RB are transmitted at both ends of
the system band. FIG. 5 shows that PUCCHs sent from two terminals
are multiplexed and occupy 2 RB resources. As shown in FIG. 6, a
method of allocating the 1 RB granularity to limit a contiguous
band may also send VoIP signals with 1 to 3 RB band widths within
any band of the system band.
Thus, if contiguous band allocation signals of one RB granularity
are less than the number of RBs consisting of RBG as a
non-contiguous band allocation unit, unused resources less than one
RBG occur as shown in FIG. 5 and FIG. 6. The conventional method of
allocating non-contiguous band cannot allocate frequency resources
less than one RBG that occurs as noted above to the terminal due to
the allocation granularity of RBG unit. Therefore the usage
efficiency of the system frequency resources decreases and the
system performance deteriorates.
An object of the present invention is to provide a radio
transmission apparatus, a radio reception apparatus, and a band
allocation method that improve the usage efficiency of the system
frequency resources and increase the system performance in
allocation of non-contiguous bands.
Solution to Problem
According to the present invention, a radio transmission apparatus
includes: a receiver configured to receive a plurality of
continuous band allocation information indicating allocation of
continuous bands; a transmission band setting unit configured to
set allocation unit boundaries of a plurality of bands allocated
using the plurality of continuous band allocation information such
that the allocation unit boundaries of the plurality of bands
differ from each other, and set a band where the plurality of bands
indicated by the plurality of continuous band allocation
information do not overlap, as a transmission band based on the
different allocation unit boundaries; and a transmitter configured
to transmit transmission data on the set transmission band.
According to the present invention, a radio reception apparatus
includes: a receiver configured to receive signals transmitted from
a communication counterpart; a band setting unit configured to set
allocation unit boundaries of a plurality of bands allocated using
a plurality of continuous band allocation information such that the
allocation unit boundaries of the plurality of bands differ from
each other, and set a band where the plurality of bands indicated
by the plurality of continuous band allocation information do not
overlap, as an allocation band based on the different allocation
unit boundaries; and an extractor configured to extract the
received signals on the set allocation band.
According to the present invention, a band allocation method
includes: setting allocation unit boundaries of a plurality of
bands allocated using a plurality of continuous band allocation
information indicating continuous band allocation, such that the
allocation unit boundaries of the plurality of bands differ from
each other; and determining a band where the plurality of bands
indicated by the plurality of continuous band allocation
information do not overlap, as a transmission band based on the set
allocation unit boundaries.
Advantageous Effects of Invention
According to the present invention, the usage rate of system
frequency resources improves and the performance of the system can
improve in allocation of non-contiguous bands.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows a tree structure of RIVs;
FIG. 2 shows contiguous band allocation and non-contiguous band
allocation;
FIG. 3 shows non-contiguous band allocation using a plurality of
RIVs disclosed in NPL 2;
FIG. 4 indicates the relationship between system bandwidth and RBG
size;
FIG. 5 illustrates a transmission mode of PUCCHs at both ends of
the system band;
FIG. 6 illustrates a transmission mode of VoIP signals within any
band of the system bands;
FIG. 7 is a block diagram illustrating the configuration of a
terminal according to Embodiment 1 of the present invention;
FIG. 8 is a block diagram illustrating the configuration of a base
station according to Embodiment 1 of the present invention;
FIG. 9 illustrates the definition of allocation unit boundaries of
each RIV;
FIG. 10 illustrates allocation bands where bands indicated by RIVs
overlap with each other;
FIG. 11 illustrates allocation bands where bands indicated by RIVs
do not overlap with each other;
FIG. 12 illustrates a band less than one RBG which is allocated
even if PUCCHs are sent at both ends of the system band;
FIG. 13 illustrates a band less than one RBG which is allocated
even if VoIPs are sent at the center of the system band;
FIG. 14 illustrates an RIV which can also indicate a band beyond
one end of the system band;
FIG. 15 is a block diagram illustrating the configuration of a
terminal according to Embodiment 2 of the present invention;
FIG. 16 illustrates non-contiguous band allocation where the
allocation unit boundaries of the RIVs are aligned;
FIG. 17 is a block diagram illustrating the configuration of a
terminal according to Embodiment 3 of the present invention;
FIG. 18 illustrates bands where the designation using RIV is
restricted;
FIG. 19 illustrates a cyclic shift of the set range of RIV within
the system band; and
FIG. 20 illustrates non-contiguous band allocation using three
RIVs.
DESCRIPTION OF EMBODIMENTS
Embodiments of the present invention will now be described in
detail with reference to drawings. Components having the same
functions in the embodiments are denoted by the same reference
numerals, and their descriptions are omitted.
Embodiment 1
FIG. 7 is a block diagram illustrating the configuration of radio
communication terminal apparatus (referred to merely as "terminal"
hereinafter) 100 according to Embodiment 1 of the present
invention. The configuration of terminal 100 is described below
with reference to FIG. 7.
RF reception unit 102 receives signals from a radio communication
base station apparatus (referred to merely as a "base station"
hereinafter) through antenna 101, performs reception processing
such as down-conversion and A/D conversion for the received
signals, and outputs the processed received signals to demodulation
unit 103.
Demodulation unit 103 demodulates scheduling information from the
base station that is included in the received signals output from
RF reception unit 102, and outputs the demodulated scheduling
information to scheduling information decoding unit 104. The
scheduling information includes, for example, frequency allocation
information, data size, power conditioner information, and the
amount of cyclic shift for a reference signal of transmission data
including RIV (contiguous band allocation information).
Scheduling information decoding unit 104 decodes the scheduling
information output from demodulation unit 103, and outputs a
plurality of RIVs included in the decoded scheduling information to
the RIV decoding unit of transmission band setting unit 105.
Transmission band setting unit 105 is provided with RIV decoding
unit 106, allocation boundary setting unit 107, and transmission
band determination unit 108. Transmission band setting unit 105
sets a transmission band to which transmission data from terminal
100 is allocated based on the plurality of RIVs output from
scheduling information decoding unit 104, and notifies mapping unit
112 of the set transmission band. The detail of transmission band
setting unit 105 will be described later.
RIV decoding unit 106 decodes a start RBG# and an end RBG#
indicated by each RIV output from scheduling information decoding
unit 104 based on an RIV tree shown in FIG. 1, and outputs the
decoded start RBG# and end RBG# to transmission band determination
unit 108.
Allocation boundary setting unit 107 outputs allocation unit
boundaries of each RIV to transmission band determination unit 108.
Here, a predetermined offset is applied to the boundaries of each
RIV in advance such that the allocation unit boundaries of each RIV
are made different from each other. The predetermined offset is
predetermined in the system. The offset may be a fixed value, or
the base station may notify a terminal in a cell of the
predetermined offset included in the system information.
Transmission band determination unit 108 determines a band
indicated by each RIV based on the start RBG# and the end RBG#
indicated by the RIV output from RIV decoding unit 106, and the
allocation unit boundaries of the RIV output from allocation
boundary setting unit 107. Transmission band determination unit 108
determines bands where the bands indicated by RIVs do not overlap
as allocation bands, and outputs the determined allocation band
information to mapping unit 112.
Encoding unit 109 encodes transmission data, and outputs the
encoded data to modulation unit 110. Modulation unit 110 modulates
the encoded data from encoding unit 109, and outputs the modulated
data signals to DFT (Discrete Fourier Transform) unit 111.
DFT unit 111 performs DFT processing for the data signals from
modulation unit 110, and outputs the data signals in the frequency
domain where the DFT processing is performed to mapping unit
112.
Mapping unit 112 maps the data signals output from the DFT unit to
frequency-domain resources according to the allocation band
information from transmission band determination unit 108, and
outputs the mapped data signals to IDFT (Inverse Discrete Fourier
Transform) unit 113.
IDFT unit 113 performs IDFT processing for the signals output from
mapping unit 112, and outputs the IDFT-processed signals to CP
(Cyclic Prefix) addition unit 114.
CP addition unit 114 adds the same signal as the tail portion of
the signals output from IDFT unit 3 to the head of the signals as a
CP, and outputs them to RF transmission unit 115.
RF transmission unit 115 performs transmission processing such as
D/A conversion, up-conversion, and amplification for the signals
output from CP addition unit 114, transmits the signals for which
the transmission processing is performed, through antenna 101.
FIG. 8 is a block diagram illustrating the configuration of base
station 200 according to Embodiment 1 of the present invention. The
configuration of base station 200 will now be described with
reference to FIG. 8.
RF reception unit 202 receives signals transmitted from the
terminals through antenna 201, performs reception processing such
as down-conversion and A/D conversion for the received signals, and
outputs the signals for which the reception processing is performed
to CP removal unit 203.
CP removal unit 203 removes the CP components added at the head of
the reception signals output from RF reception unit 202, and
outputs the signals to DFT unit 204.
DFT unit 204 performs DFT processing for the received signals from
CP removal unit 203 to transform them into frequency-domain
signals, and outputs the signals transformed into the frequency
domain to demapping unit 207.
Scheduling information holding unit 205 holds the scheduling
information which has been sent to the terminals, and outputs the
scheduling information of a desired terminal to be received to
transmission band setting unit 206.
Similar to transmission band setting unit 105 provided by terminal
100 shown in FIG. 7, transmission band setting unit 206 sets the
allocation band information of the desired terminal based on the
scheduling information from scheduling information holding unit
205, and notifies demapping unit 207 of the set allocation band
information.
Demapping unit 207 as extraction means extracts signals
corresponding to the transmission band of the desired terminal from
the frequency-domain signals output from DFT unit 204 according to
the allocation band information indicated by transmission band
setting unit 206, and outputs the extracted signals to
frequency-domain equalization unit 208.
Frequency-domain equalization unit 208 performs equalization for
the signals from demapping unit 207, and outputs the equalized
signals to IDFT unit 209. IDFT unit 209 performs IDFT processing
for the signals output from frequency-domain equalization unit 208,
and outputs the IDFT-processed signals to demodulation unit
210.
Demodulation unit 210 demodulates the signals output from IDFT unit
209, and outputs the demodulated signals to decoding unit 211.
Decoding unit 211 decodes the signals from demodulation unit 210,
and extracts the received data.
The operation of transmission band setting unit 105 of terminal 100
described above will now be explained. Allocation boundary setting
unit 107 makes the allocation unit boundaries of a plurality of
RIVs different from each other, and determines bands where the
plurality of bands indicated by RIVs do not overlap as allocation
bands. Further details will be described hereinafter.
The allocation units (equal to RBG) of the plurality of RIVs are
predefined such that boundaries thereof differ from each other.
More specifically, as shown in FIG. 9, a different offset (value
less than one RBG) is added at a position (reference position) as
reference of band indicated by each RIV. For example, when the
number of RIVs is equal to 2 (RIV #1 and RIV #2) and 1 RBG=4 RB,
the offset of RIV #1 is defined as zero, and the offset of RIV #2
is defined as +2 RB (=+RBG/2) or -2 RB (=-1 RBG/2), with the
reference position fixed as shown in FIG. 9. As a result, a
different offset is added to the band indicated by each RIV,
thereby enabling shifting of allocation unit boundaries of
RIVs.
The reference position of the band indicated by each RIV is
predetermined by the terminal and the base station. The reference
position would be, for example, on the far right or left of the
system band, in the band adjacent to PUCCH areas, or on the far
tight or left of a SRS (Sounding Reference Signal) transmission
area.
The amplitude (set range) of the band that can be indicated by each
RIV is also predetermined by the terminal and the base station.
Defining the set range of each RIV so as to allocate the overall
system band will provide the highest degree of freedom of
allocation. Also, defining the set range of each RIV as part of the
system band can reduce the number of signaling bits because of
decreased RIV values. It is, however, required to define the set
range of each RIV so that areas where the set ranges of RIVs
overlap are provided in this case.
Transmission band determination unit 108 then derives the band
indicated by each RIV according to the definition of RBG described
above, and determines bands where the plurality of bands indicated
by RIVs do not overlap as allocation bands (transmission bands).
That is, assuming that the bands (that are within a range from the
start RBG# to the end RBG#) indicated by RIVs are equal to "1", and
the bands other than that are equal to "0", the bands that are
equal to "1" as a result of performing the XOR (exclusive OR)
operation on bands indicated by RIVs are determined as the
allocation bands.
An allocation band determination method will be described with
reference to FIG. 10 and FIG. 11, where the number of RIVs is, for
example, equal to 2 (RIV #1 and RIV #2) and 1 RBG=4 RB. When bands
indicated by RIVs overlap, as shown in FIG. 10, bands where they do
not overlap are determined as the allocation bands, thereby
enabling designation of non-contiguous band allocation with a
bandwidth of 2 RB (=1 RBG/2). When bands indicated by RIVs do not
overlap, as shown in FIG. 11, the indicated bands themselves are
determined as the allocation bands in a conventional manner. Thus,
in any case, whether or not the bands indicated by RIVs overlap, a
single rule of "bands where bands indicated by a plurality of RIVs
do not overlap are determined as allocation bands" determines the
allocation bands.
Here, even if the band allocation shown in FIG. 10 and FIG. 11 is
applied to different terminals, no unnecessary empty resources
remain in the system band, and the terminals can be
frequency-multiplexed at the same time.
The notification method of indicating non-contiguous band
allocation using a plurality of RIVs thus makes allocation unit
boundaries of the plurality of RIVs different from each other, and
determines bands where the bands indicated by the RIVs do not
overlap as the allocation bands, thereby enabling the indication of
non-contiguous band allocation including contiguous band allocation
of bandwidths less than one RBG, and thus enabling improvement in
the usage efficiency of the system frequency resources.
Thus, even if PUCCHs are transmitted at both ends of the system
band as shown in FIG. 5, the bands indicated by RIVs are sent with
overlapped as shown in FIG. 12, thereby enabling allocation of a
band less than one RBG.
Similarly, even if WO signals are transmitted at the center of the
system band as shown in FIG. 6, bands indicated by RIVs are sent
with overlapped as shown in FIG. 13, thereby enabling a band less
than one RBG.
Thus Embodiment 1 makes the allocation unit boundaries of the
plurality of RIVs different from each other, and determines bands
where the bands indicated by RIVs do not overlap as the allocation
bands. This enables the indication of non-contiguous band
allocation including the contiguous band allocation of bandwidths
less than one RBG, and thus enabling improvement in the usage
efficiency of the system frequency resources, thereby enabling
improvement in the system performance.
As shown in FIG. 14, if RIV #1 can indicate a band beyond one end
of the system band and RIV #2 can also indicate a band to the other
end of the system band, the allocation of the number of clusters
(the number of contiguous band blocks) less than the number of RIVs
can be indicated, thus enabling resource allocation less than one
RBG in a single cluster.
Since the resource allocation less than one RBG can be provided
over the whole transmission bandwidth, cell-edge terminals with
marginal transmission power can reduce performance degradation due
to the lack of transmission power. This point is specifically
described herein. Acquiring desired reception quality requires an
increase in the transmission power of a terminal in proportion to
the entire transmission bandwidth of transmission data, while
cell-edge terminals located far from the base station need
transmission power close to the maximum transmission power for the
pathless compensation. Such terminals are subject to the limitation
of the maximum transmission power, and are cannot transmit signals
with a high transmission bandwidth using the required transmission
power. Thus, the shortage of terminal transmission power hinders
the acquisition of desired reception quality, and results in the
performance degradation. Providing the resource allocation less
than one RBG over the whole transmission bandwidth can therefore
reduce such performance degradation.
Embodiment 2
FIG. 15 is a block diagram illustrating the configuration of
terminal 300 according to Embodiment 2 of the present invention,
FIG. 15 differs from FIG. 7 in that scheduling information decoding
unit 104 and allocation boundary setting unit 107 are replaced with
scheduling information decoding unit 301 and allocation boundary
setting unit 302, respectively.
Scheduling information decoding unit 301 decodes scheduling
information output from demodulation unit 103, and outputs a
plurality of RIVs included in the decoded scheduling information to
RIV decoding unit 106 of transmission band setting unit 105.
Scheduling information decoding unit 301 also outputs offset
information that determines the allocation unit boundaries of each
RIV included in the scheduling information from demodulation unit
103 to allocation boundary setting unit 302.
Allocation boundary setting unit 302 determines the allocation unit
boundaries of each RIV based on the offset information from
scheduling information decoding unit 301, and outputs the
determined allocation unit boundaries of each RIV to transmission
band determination unit 108.
The configuration of the base station according to Embodiment 2 of
the present invention is similar to the configuration according to
Embodiment 1 shown in FIG. 8, except that the transmission band
setting unit has a different function. The transmission band
setting unit is similar to transmission band setting unit 105
provided by terminal 300 shown in FIG. 15.
The operation of transmission band setting unit 105 of terminal 300
described above will now be described. The base station first
notifies terminal 300 of the offset information of one bit
indicating whether or not the allocation unit boundaries of a
plurality of RIVs are made different as the scheduling information.
Terminal 300 determines the allocation unit boundaries of each RIV
in allocation boundary setting unit 302 of transmission band
setting unit 105 based on the offset information.
When the offset information indicates that the boundaries are made
different, allocation boundary setting unit 302 makes the
boundaries different from each other by adding a predetermined
offset to the allocation unit boundaries of each RIV. For example,
when the number of RIVs is equal to 2 (RIV #1 and RIV #2) and 1
RBG=4 RB, the offset of RIV #1 is defined as zero, and the offset
of RIV #2 is defined as +2 RB (=+RBG/2) or -2 RB (=-1 RBG/2), as
shown in FIG. 9. As a result, the allocation unit boundaries of
RIVs are shifted, thereby enabling the band allocation of RBG/2 as
described in Embodiment 1.
On the other hand, when the offset information indicates that the
boundaries are not made different, allocation boundary setting unit
302 aligns boundaries without addition of the offsets to the
allocation unit boundaries of each RIV.
After determining the allocation boundaries, transmission band
setting unit 105 performs similar processing as in Embodiment 1,
i.e., determines bands where the bands indicated by a plurality of
RIVs do not overlap as allocation bands, and outputs the determined
allocation band information to mapping unit 112.
The amount of offset may be sent as the offset information. While
the number of bits to be sent increases, the degree of freedom of
frequency scheduling improves.
Here, the base station sets, according to the situation, the offset
information indicating whether or not allocation unit boundaries of
RIVs are made different. That is, when the system band has a large
number of contiguous empty resources, aligning the allocation unit
boundaries of the plurality of RIVs of each terminal as shown in
FIG. 16 facilitates the frequency scheduling of the terminals in a
cell using non-contiguous band allocation. In this manner, the
frequency scheduling method can easily prevent the occurrence of
unnecessary empty resources. On the other hand, when the system
band does not have a large number of contiguous empty resources,
making the allocation unit boundaries of RIVs as shown in
Embodiment 1 can improve the usage efficiency of the system
frequency resources.
Thus, Embodiment 2 sets whether or not the allocation unit
boundaries of each RIV are made different according to the number
of contiguous empty resources existing in the system band. When the
system band has a large number of contiguous empty resources,
aligning the allocation unit boundaries of the plurality of RIVs of
each terminal can facilitate the frequency scheduling of the
terminals in a cell using the non-contiguous band allocation,
thereby enabling prevention of the occurrence of unnecessary empty
resources.
Embodiment 3
FIG. 17 is a block diagram illustrating the configuration of
terminal 400 according to Embodiment 3 of the present invention.
FIG. 17 differs from FIG. 7 in that RIV decoding unit 106 and
allocation boundary setting unit 107 are replaced with RIV decoding
unit 401 and allocation boundary setting unit 402,
respectively.
RIV decoding unit 401 decodes the start RBG# and the end RBG#
indicated by each RIV output from scheduling information decoding
unit 104 based on the RIV tree shown in FIG. 1, and outputs the
decoded start RBG# and end RBG# to allocation boundary setting unit
402 and transmission band determination unit 108.
Allocation boundary setting unit 402 determines the allocation unit
boundaries of each RIV based on the start RBG# and the end RBG#
output from RIV decoding unit 401, and outputs the determined
allocation unit boundaries of each RIV to transmission band
determination unit 108.
The configuration of the base station according to Embodiment 3 of
the present invention is similar to the configuration of Embodiment
1 shown in FIG. 8, except that the transmission band setting unit
has a different function. The transmission band setting unit is
similar to transmission band setting unit 105 provided by terminal
400 shown in FIG. 17.
The operation of transmission band setting unit 105 of terminal 400
described above will now be described. Allocation boundary setting
unit 402 of transmission band setting unit 105 determines whether
making allocation unit boundaries of RIVs different or not
depending on whether ranges from the start RBG#s to the end RBG#s
of RIVs overlap with each other or not. That is, the offset
information is defined according to whether the respective ranges
of the RBG numbers indicated by RIVs overlap with each other.
When the ranges of the RBG numbers indicated by RIVs overlap to
each other, a predetermined offset is added to the allocation unit
boundaries of each RIV to make the boundaries different. Similarly
to Embodiment 1 and Embodiment 2, the method of making the
boundaries different to each other is to add a predetermined amount
of offset (less than one RBG) to the allocation unit boundaries of
each RIV.
In contrast, when the ranges of the RBG numbers indicated by RIVs
do not overlap with each other, the allocation unit boundaries of
RIVs are aligned (no offsets are added).
After thus determining the allocation boundaries, transmission band
setting unit performs similar processing as in Embodiment 1, i.e.,
determines bands where the bands indicated by a plurality of RIVs
do not overlap, as the allocation bands, and outputs the determined
allocation band information to the mapping unit.
Thus, notice of the offset information to be sent depending on
whether the ranges of the RBG numbers indicated by RIVs overlap
with each other or not can have the similar effect as Embodiment 2
without additional signaling. That means, when the system band has
a large number of contiguous empty resources, aligning the
allocation unit boundaries of the plurality of RIVs of each
terminal facilitates the frequency scheduling of the terminals in a
cell using the non-contiguous band allocation, thereby enabling
prevention of the occurrence of the unnecessary empty
resources.
Thus, Embodiment 3 sends the offset information depending on
whether the ranges of the RBG numbers indicated by RIVs overlap
with each other or not, thereby making it possible to set whether
the allocation unit boundaries of RIVs are made different to each
other or not according to the number of the contiguous empty
resources existing in the system band, without additional
signaling.
Embodiment 4
The configuration of terminals and the configuration of a base
station according to Embodiment 4 of the present invention are
similar to the corresponding configurations according to Embodiment
1 shown in FIG. 7 and FIG. 8, except that a transmission band
setting unit has a different function. Therefore, the transmission
band setting unit will now be described.
Here, the number of signaling bits necessary to send RIVs is
described, Assuming the total number of RBG#s indicating allocation
bandwidths that can be indicated by RIVs to be N.sub.RBG, the
number S of the signaling bits necessary to send a piece of RIV
information is represented by the following Equation 1:
S[bit]=Roundup(log.sub.2(N.sub.RBG(N.sub.RBG+1)/2)) (Equation
1)
In Equation 1, "Roundup ( )" indicates the process of rounding up a
decimal value in the parentheses. Equation 1 shows that the larger
N.sub.RBG is, the more the number S of the signaling bits
increases.
Thus, as shown in FIG. 18, limiting the allocation bandwidths that
can be indicated by RIVs below the system bandwidth would decrease
the N.sub.RBG and reduce the number S of the signaling bits. In
FIG. 18, there is a limit that RIV #1 and RIV #2 cannot indicate
the far right and left of the system band, respectively.
If the allocation bandwidths that can be indicated by RIVs are
limited to the system bandwidth or less to reduce the signaling
bits as described above, the band less than one RBG cannot be
allocated in the band where bands indicated by RIVs do not overlap.
That is, if the allocation bandwidths that can be indicated by RIVs
are limited as shown in FIG. 18, a band less than one RBG cannot be
allocated in the both ends of the system band.
In spite of this assumption, since PUCCHs or VoIP signals are
generally allocated in the both ends of the system band, small
empty resources readily occur therein. The small empty resources
occurring in the both ends of the system band cannot be allocated
and not effectively used as a result.
If the allocation bandwidths that can be indicated by RIVs are
limited to the system band or less, transmission band determination
unit 108 adopts a band that cannot be indicated by RIVs as the
central area of the system band. Transmission band determination
unit 108 also cyclically shifts RBG# indicated by each RIV in the
system band, where the definition of RIV is shared among the
terminals and the base stations by being predefined in the system
or by being defined at each base station.
FIG. 19 illustrates an example of the RIV definition described
above. The band that cannot be indicated by each RIV is set in the
central area of the system baud, and each RIV can indicate the
corresponding end of the system band. For example, the indications
beyond the system band such as a start RBG=5 and an end RBG=6 of
RIV #1 and a start RBG=1 and an end RBG=2 of RIV #2 are made by
cyclically shifting RBG#s in the system band, thereby indicating
RBGs in the both ends of the system baud.
This can indicate the both ends of the system band where a large
number of small empty resources occur using RIVs even if the
allocation bandwidths that can be indicated by RIVs are limited
below the system hand, thus enabling improvement in the usage
efficiency of the system frequency resources without increasing the
number of the signaling bits.
Thus, according to Embodiment 4, if the allocation bandwidths that
can be indicated by RIVs are limited to the system band or less,
the band that cannot be indicated by RIVs is adopted as the central
area of the system band, and RBG# (set range of RIV) indicated by
each RIV is cyclically shifted in the system band, thereby making
it possible to indicate the both ends of the system band using each
RIV and thus to improve the usage efficiency of the system
frequency resources.
Here, the above embodiments are described as an example where the
number of RIVs to be sent is two. However, the number of RIVs may
be three or more. For example, FIG. 20 illustrates non-contiguous
band allocation using three RIVs. In FIG. 20, RBG of RIV #1 is
equal to 4 RB, and RBGs of RIV #2 and RIV #3 whose set ranges are
part of the system band are equal to 2 RB. As described in
Embodiment 1, RBG boundaries of RIV #1, RIV #2 and RIV #3 are
defined so as to be different from one another. Even if PUCCHs each
having the allocation granularity of 1 RB are sent at both ends of
the system band, the bands indicated by the RIVs are sent with
overlapped as shown in FIG. 20, thereby allocating a band less than
one RBG.
While the present invention is described with reference to hardware
in the embodiments, the present invention may be implemented using
software.
Each function block employed in the description of each of the
aforementioned embodiments are typically be implemented as an LSI
constituted by an integrated circuit. These may be individual chips
or partially or totally contained on a single chip. "LSI" is
adopted here but this may also be referred to as "IC," "system
LSI," "super LSI," or "ultra LSI" depending on differing extents of
integration.
Furthermore, the method of circuit integration is not limited to
LSI's, and implementation using dedicated circuitry or general
purpose processors is also possible. After LSI manufacture,
utilization of a programmable FPGA (Field Programmable Gate Array)
or a reconfigurable processor where connections and settings of
circuit cells within an LSI can be reconfigured is also
possible.
Furthermore, if integrated circuit technology comes out to replace
LSI's as a result of the advancement of semiconductor technology or
a different technology derived from the semiconductor technology,
it is naturally also possible to carry out function block
integration using this technology. Application of biotechnology is
also possible.
Here, although the antenna is described in the above embodiments,
the present invention can be applied to a case where an antenna
port is used.
The antenna port refers to a logical antenna that is provided with
a single or a plurality of physical antennas. That is, the antenna
port does not necessarily refer to a single physical antenna, but
may refer to, for example, an array antenna formed of a plurality
of antennas.
For example, 3GPP LTE does not define the number of physical
antennas that configure the antenna port, but a minimum unit for a
base station to transmit a different reference signal.
The antenna port may also be defined as a minimum unit for
multiplication of the weight of a precoding vector.
The disclosure of Japanese Patent Application No. 2010-3154, filed
on Jan. 8, 2010 including the specification, drawings and abstract,
is incorporated herein by reference in its entirely.
INDUSTRIAL APPLICABILITY
The radio transmission apparatus, the radio reception apparatus,
and the band allocation method according to the present invention
are applicable, for example, to a mobile communication system such
as LTE-Advanced.
REFERENCE SIGNS LIST
101, 201: Antenna 102, 202: RF reception unit 103, 210:
Demodulation unit 104, 301: Scheduling information decoding unit
105, 206: Transmission band setting unit 106, 401: RIV decoding
unit 107, 302, 402: Allocation boundary setting unit 108:
Transmission band determination unit 109: Encoding unit 110:
Modulation unit 111, 204: DFT unit 112: Mapping unit 113, 209: IDFT
unit 114: CP addition unit 115: RF transmission unit 203: CP
removal unit 205: Scheduling information holding unit 207:
Demapping unit 208: Frequency-domain equalization unit 211:
Decoding unit
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