`
`(12) United States Patent
`US 8,102,833 B2
`(10) Patent N0.:
`Lee et al.
`
`(45) Date of Patent: Jan. 24, 2012
`
`(54)
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`(75)
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`(73)
`(*)
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`(21)
`(22)
`(65)
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`(60)
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`METHOD FOR TRANSMITTING UPLINK
`SIGNALS
`
`Inventors: Dae Won Lee, Gyeonggi-do (KR); Bong
`Hoe Kim, Gyeonggi-do (KR); Young
`Woo Yun, Gyeonggi-do (KR); Ki Jun
`Kim, Gyeonggi-do (KR); Dong Wook
`Roh, Gyeonggi-do (KR); Hak Seong
`Kim, Gyeonggi-do (KR); Hyun Wook
`Park, Gyeonggi-do (KR)
`LG Electroics Inc., Seoul (KR)
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 725 days.
`Appl. No.: 12/209,136
`Filed:
`Sep. 11, 2008
`Prior Publication Data
`
`Assignee:
`Notice:
`
`US 2009/0097466 A1
`
`Apr. 16, 2009
`
`Related US. Application Data
`
`Provisional application No. 60/972,244, filed on Sep.
`13, 2007, provisional application No. 60/987,427,
`filed on Nov. 13, 2007, provisional application No.
`60/988,433, filed on Nov. 16, 2007.
`
`(30)
`
`Foreign Application Priority Data
`
`Jul. 15,2008
`
`(KR) ........................ 10-2008-0068634
`
`(51)
`
`(52)
`(58)
`
`Int. Cl.
`
`(2006.01)
`H043 7/208
`US. Cl.
`........................................ 370/344; 370/319
`Field of Classification Search .................. 370/206,
`370/278, 344, 208, 252, 294, 295, 315, 319,
`370/328, 329, 330, 335, 336, 338; 455/450,
`455/509
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`2003/0185159 A1* 10/2003 Seo et al.
`...................... 370/278
`2005/0232138 A1
`10/2005 Byun et al.
`2005/0286402 A1
`12/2005 Byun et al.
`2006/0098568 A1*
`5/2006 Oh et al.
`....................... 370/206
`2008/0304467 A1 * 12/2008 Papasakellariou et a1.
`370/344
`FOREIGN PATENT DOCUMENTS
`1569403
`8/2005
`1806867
`7/2007
`1811701
`7/2007
`10-2004-0056976
`7/2004
`10-2005-0114569
`12/2005
`
`EP
`EP
`EP
`KR
`KR
`
`* cited by examiner
`
`Primary Examiner 7 Derrick Ferris
`Assistant Examiner 7 Mang Yeung
`(74) Attorney, Agent, or Firm 7 Lee, Hong, Degerrnan,
`Kang & Waimey
`
`(57)
`
`ABSTRACT
`
`A method for transmitting uplink signals, which include
`ACK/NACK signals, control signals other than the ACK/
`NACK signals, and data signals, is disclosed. The method
`comprises serially multiplexing the control signals and the
`data signals; sequentially mapping the multiplexed signals
`within a specific resource region in accordance with a time-
`first mapping method, the specific resource region including
`a plurality of symbols and a plurality of virtual subcarriers;
`and arranging the ACK/NACK signals at both symbols near
`symbols to which a reference signal of the plurality of sym-
`bols is transmitted. Thus, the uplink signals can be transmit-
`ted to improve receiving reliability of signals having high
`priority.
`
`See application file for complete search history.
`
`14 Claims, 9 Drawing Sheets
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`Postion which Punctures Data modulation
`Symbols
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`E1
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`APPLE 1001
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`
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`U.S. Patent
`
`Jan. 24, 2012
`
`Sheet 1 of 9
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`US 8,102,833 B2
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`U.S. Patent
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`Jan. 24, 2012
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`Sheet 2 of 9
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`US 8,102,833 B2
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`UL ACK/ NACK Signaling
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`Jan. 24, 2012
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`Sheet 3 of 9
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`US 8,102,833 B2
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`U.S. Patent
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`Jan. 24, 2012
`
`Sheet 4 of 9
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`US 8,102,833 B2
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`FIG. 4
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`Jan. 24, 2012
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`Sheet 5 019
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`Jan. 24, 2012
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`Sheet 6 of9
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`US 8,102,833 B2
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`Sheet 7 of9
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`US 8,102,833 B2
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`US 8,102,833 B2
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`FIG.
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`U.S. Patent
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`Jan. 24, 2012
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`Sheet 9 of 9
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`US 8,102,833 B2
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`US 8,102,833 B2
`
`1
`METHOD FOR TRANSMITTING UPLINK
`SIGNALS
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`This application claims the benefit of the Korean Patent
`Application No. 10-2008-0068634, filed on Jul. 15, 2008,
`which is hereby incorporated by reference as if fully set forth
`herein.
`
`This application also claims the benefit ofUS. Provisional
`Application Ser. Nos. 60/972,244, filed on Sep. 13, 2007,
`60/987,427, filed on Nov. 13, 2007 and 60/988,433, filed on
`Nov. 16, 2007, the contents of which are hereby incorporated
`by reference herein in their entirety.
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`
`The present invention relates to mobile communication
`technology, and more particularly, to technology of transmit-
`ting uplink signals including ACK/NACK signals, control
`signals other than the ACK/NACK signals, and data signals.
`2. Discussion of the RelatedArt
`
`A user equipment (UE) of a mobile communication system
`transmits various signals through an uplink. Uplink signals
`transmitted by the user equipment can be segmented into data
`signals and control signals. Also, examples of the control
`signals transmitted to the uplink include uplink ACK/NACK
`signals for HARQ communication, channel quality indicator
`(CQI) information, and preceding matrix index (PMI).
`3GPP LTE system uses a single carrier frequency division
`multiplexing access (SC-FDMA) scheme for uplink signal
`transmission. Also, the 3GPP LTE system prescribes that data
`signals and control signals among the uplink signals are first
`multiplexed and ACK/NACK signals are transmitted to the
`multiplexed signals by puncturing the data or control signals
`when uplink ACK/NACK signal transmission is required for
`downlink data. Hereinafter, in order that the ACK/NACK
`signals are divided from control signals other than the ACK/
`NACK signals, the control signals will mean those except for
`the ACK/NACK signals.
`Meanwhile, Athens conference (#50) for 3GPP LTE has
`decided that data information is rate matched together with
`control information when the control information is multi-
`
`plexed with the data information, wherein the control infor-
`mation is transmitted near a reference signal. This is to
`improve channel estimation performance by approximating
`all the control signals to the reference signal as the control
`signals generally require higher reliability than the data sig-
`nals.
`
`However, the control signals transmitted to the uplink
`include various signals as described above, and the ACK/
`NACK signals require higher reliability than the other control
`signals. In this case, when uplink ACK/NACK signal trans-
`mission is required while all the control signals are transmit-
`ted by approximating to the reference signal, problems occur
`in that the ACK/NACK signals can neither be transmitted by
`puncturing the control signals arranged near the reference
`signal nor be transmitted near the reference signal.
`In this respect, a technology of transmitting uplink signals
`by efiiciently arranging ACK/NACK signals and other con-
`trol signals in a resource region considering priority among
`them is required.
`
`10
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`2
`SUMMARY OF THE INVENTION
`
`Accordingly, the present invention is directed to a method
`for transmitting uplink signals, which substantially obviates
`one or more problems due to limitations and disadvantages of
`the related art.
`
`An object of the present invention is to provide a method
`for transmitting uplink signals by efiiciently arranging ACK/
`NACK signals and other control signals in a resource region
`considering priority among them.
`Another object of the present invention is to provide trans-
`mitting uplink signals using the aforementioned signal
`arrangement.
`To achieve these objects and other advantages and in accor-
`dance with the purpose of the invention, as embodied and
`broadly described herein, the present invention provides a
`method for transmitting uplink signals, which include ACK/
`NACK signals, control signals other than the ACK/NACK
`signals, and data signals. The method comprises serially mul-
`tiplexing the control signals and the data signals; sequentially
`mapping the multiplexed signals within a specific resource
`region in accordance with a time-first mapping method, the
`specific resource region including a plurality of symbols and
`a plurality of virtual subcarriers; and arranging the ACK/
`NACK signals at both symbols near to symbols through
`which a reference signal is transmitted.
`At this time, the ACK/NACK signals are overwritten on a
`part of the multiplexed signals. And, the part of the multi-
`plexed signals, on which the ACK/NACK signals are over-
`written, includes one or more of the control signals and the
`data signals.
`Also, the method further comprises performing a discrete
`fourier transform (DFT) for the signals mapped on the spe-
`cific resource region in a unit of each symbols ofthe plurality
`of symbols in accordance with each index of the plurality of
`virtual subcarriers; performing an inverse fast fourier trans-
`form (IFFT) for the DFT symbol unit signals and attaching a
`cyclic prefix (CP) the signals; and transmitting the symbol
`unit signals attached with the CP as single carrier frequency
`division multiplexing access (SC-FDMA) symbols.
`Also, the method further comprises transmitting the sig-
`nals mapped on the specific resource region through a physi-
`cal uplink sharing channel (PUSCH).
`In another aspect of the present invention, the present
`invention provides a method for transmitting uplink signals,
`which include ACK/NACK signals, control signals other than
`the ACK/NACK signals, and data signals. The method com-
`prises performing channel coding for each of the data signals,
`the control signals, and theACK/NACK signals; serially mul-
`tiplexing the channel coded data and control signals; sequen-
`tially mapping the multiplexed signals in accordance with a
`time-first mapping method within a specific resource region
`in accordance with a time-first mapping method, the specific
`resource region including a plurality of symbols and a plural-
`ity of virtual subcarriers; and arranging the ACK/NACK sig-
`nals at both symbols near to the symbols through which a
`reference signal is transmitted.
`At this time, the step of performing channel coding for the
`data signals includes attaching a CRC for a transport block
`(TB) to a transport block for transmission of the data signals;
`segmenting the transport block attached with the CRC for the
`transport block in a code block unit and attaching a CRC for
`a code block to the segmented code block; performing chan-
`nel coding for the data attached with the CRC for a code
`block; and performing rate matching and code block concat-
`enation for the channel coded data.
`
`
`
`US 8,102,833 B2
`
`3
`According to the aforementioned embodiments of the
`present invention, it is possible to transmit uplink signals by
`efiiciently arranging ACK/NACK signals and other control
`signals in a resource region in accordance with priority
`among them.
`In addition, the ACK/NACK signals having high priority
`can be set in such a manner that they acquire more channel
`estimation effect.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`The accompanying drawings, which are included to pro-
`vide a further understanding of the invention and are incor-
`porated in and constitute a part of this specification, illustrate
`embodiments of the invention and together with the descrip-
`tion serve to explain the principles of the invention.
`In the drawings:
`FIG. 1 is a block diagram illustrating a transmitter to
`describe a method for transmitting signals in accordance with
`a single carrier frequency division multiplexing access (SC-
`FDMA) scheme;
`FIG. 2 is a diagram illustrating a procedure ofmultiplexing
`data information, control information and ACK/NACK sig-
`nals for uplink signal transmission;
`FIG. 3 is a diagram illustrating an example of mapping
`information sequences according to one embodiment of the
`present invention in accordance with a time-first mapping
`method
`
`FIG. 4 and FIG. 5 are diagrams illustrating a method for
`transmitting information, which is mapped in accordance
`with the time-first mapping method as illustrated in FIG. 3, in
`accordance with the SC-FDMA scheme;
`FIG. 6 is a diagram illustrating a method for transmitting
`uplink signals in accordance with one embodiment of the
`present invention;
`FIG. 7 and FIG. 8 are diagrams illustrating a method for
`processing a number of ACK/NACK information data to be
`transmitted in accordance with one embodiment of the
`
`present invention; and
`FIG. 9 is a diagram illustrating thatACK/NACK signals are
`inserted by puncturing the control signals as well as the data
`signals in accordance with another embodiment ofthe present
`invention.
`
`DETAILED DESCRIPTION OF THE INVENTION
`
`the preferred embodiments of the present
`Hereinafter,
`invention will be described with reference to the accompany-
`ing drawings. It is to be understood that the detailed descrip-
`tion, which will be disclosed along with the accompanying
`drawings, is intended to describe the exemplary embodiments
`of the present invention, and is not intended to describe a
`unique embodiment with which the present invention can be
`carried out. Hereinafter, the following detailed description
`includes detailed matters to provide full understanding of the
`present invention. However,
`it will be apparent to those
`skilled in the art that the present invention can be carried out
`without the detailed matters.
`
`Meanwhile, in some cases, to prevent the concept of the
`present
`invention from being ambiguous, structures and
`apparatuses ofthe known art will be omitted, or will be shown
`in the form of a block diagram based on main functions of
`each structure and apparatus. Also, wherever possible, the
`same reference numbers will be used throughout the draw-
`ings and the specification to refer to the same or like parts.
`As described above, the embodiment of the present inven-
`tion is intended to provide a method for transmitting uplink
`
`10
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`15
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`20
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`25
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`30
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`35
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`50
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`60
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`65
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`4
`
`signals by efiiciently arranging ACK/NACK signals and
`other control signals in a resource region considering priority
`among them. To this end, a detailed method for transmitting
`uplink signals in a 3GPP LTE system will be described.
`FIG. 1 is a block diagram illustrating a transmitter to
`describe a method for transmitting signals in accordance with
`a single carrier frequency division multiplexing access (SC-
`FDMA) scheme.
`As described above, a 3GPP LTE system transmits uplink
`signals in accordance with a single carrier frequency division
`multiplexing access (SC-FDMA) scheme. In detail, direct-to-
`parallel conversion is performed for information sequences to
`be transmitted, to perform a discrete fourier transform (DFT)
`(101). The DFT is performed for the signals converted to the
`parallel sequences (102), and then inverse fast fourier trans-
`form (IFFT) can be performed to obtain a single carrier fea-
`ture (103). At this time, a length of information inserted to an
`IFFT module 103 may not be equal to a size of the IFFT
`module 103. However, it is required that the DFT result per-
`formed by the DFT module 102 should be mapped with
`continuous IFFT input indexes.
`Values undergone IFFT are again converted to serial sig-
`nals by a parallel-to-serial conversion module 104. After-
`wards, the signals are changed to a format of OFDM symbols
`by a cyclic prefix (CP) (105) and then transmitted to a real
`time space.
`The aforementioned SC-FDMA scheme has advantages in
`that it has low peak power-to-average power ratio (PAPR)
`and/or cubic metric (CM) while maintaining a single carrier
`feature. However, in order to satisfy low PAPR/CM condition
`while maintaining a single carrier feature, it is required that
`information undergone DFT preceding should be input to the
`IFFT module 103 in an OFDM format by mapping with
`continuous indexes. In other words, it is required that DFT
`precoded information should be inserted to continuous sub-
`carriers of OFDM. Accordingly, it is preferable that informa-
`tion data (for example, control information and data informa-
`tion) having different features are multiplexed together when
`they are transmitted to an uplink so that they undergo DFT
`precoding together and then are transmitted in an OFDM
`format.
`
`Hereinafter, a procedure of multiplexing data information
`and control information will be described.
`
`FIG. 2 is a diagram illustrating a procedure ofmultiplexing
`data information, control information and ACK/NACK sig-
`nals for uplink signal transmission.
`Data information multiplexed with control information is
`segmented into several code blocks (CB) in accordance with
`a size of a transport block (TB) to be transmitted to the uplink
`after CRC for TB is attached to the TB ($201 and $202).
`Afterwards, the CRC for CB is attached to several CBS
`(8203), and channel coding is performed for the result value
`obtained by attaching the CRC for CB to several CBS (8204).
`Also, after the channel coded data undergo rate matching
`($205), concatenation among CBs is performed ($206). The
`CBs are then multiplexed with control information (8230).
`Meanwhile, the aforementioned steps may be subject to chan-
`nel coding chain for a data transport block.
`Channel coding can be performed for the control informa-
`tion separately from the data information ($211). The channel
`coded control information can later be multiplexed with the
`data information by a data and control channel rate mapping
`multiplexer (8230).
`Channel coding can be performed for the ACK/NACK
`signals separately from the data and control signals (8221).
`Some of the uplink signals in which the data and control
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`signals are multiplexed (8230) may be transmitted to the
`uplink through puncturing (8240).
`As described above, the control information that can be
`transmitted together with the data information is segmented
`into two types,
`i.e., uplink (UL) ACK/NACK signals for
`downlink data and other control information. The uplink
`ACK/NACK signals for downlink data are transmitted only
`when downlink data exist. A user equipment may not know
`whether to receive downlink data even though it should trans-
`mit the UL ACK/NACK signals. Accordingly, the user equip-
`ment segments the two types of control information from
`each other and transmits them to the uplink together with the
`data information. Hereinafter, in order to segment the ACK/
`NACK signals from the control signals transmitted separately
`from the ACK/NACK signals, “control signals” will mean
`those other than the ACK/NACK signals. In more detailed
`embodiment, the control signals may mean those other than a
`rank indicator as well as the ACK/NACK signals. In other
`words, in a specific embodiment, the control signals may
`include CQI and PMI. However, since the following descrip-
`tion relates to efficient arrangement among the control sig-
`nals, the data signals and the ACK/NACK signals, if the
`control signals are those other than the ACK/NACK signals,
`their detailed type will not be suggested.
`When the data information is transmitted to the uplink, the
`data information can be transmitted together with the control
`information. Also, ACK/NACK information can be transmit-
`ted together with the data information and the control infor-
`mation. Moreover, only the data information and the ACK/
`NACK information can be transmitted to the uplink.
`Transmission information sequences obtained to transmit
`the data information multiplexed with the control information
`or the ACK/NACK information can be transmitted in accor-
`dance with the SC-FDMA scheme. At this time, the transmis-
`sion information sequences can be mapped in a resource
`region in accordance with a time-first mapping method.
`For example, it is supposed that the information sequences
`are transmitted using one resource block, i.e., twelve (12)
`OFDM subcarriers and information is transmitted through
`one sub-frame. Also,
`it
`is supposed that one sub-frame
`includes fourteen (14) SC-FDMA symbols and two of the
`fourteen SC-FDMS symbols are used as references signals
`that are pilot signals. At this time, the number of modulation
`symbols of the information that can be transmitted to the
`uplink becomes 12*12:144.
`144 information sequence symbols can be transmitted
`through 12 virtual subcarriers and 12 SC-FDMA symbols.
`This can be represented by a matrix structure of 12*12 called
`a time-frequency mapper. The information sequences to be
`transmitted to the uplink are mapped one by one based on the
`SC-FDMA symbols. This is called time-first mapping
`because the SC-FDMA symbols are segmented temporally.
`FIG. 3 is a diagram illustrating an example of mapping
`information sequences according to one embodiment of the
`present invention in accordance with a time-first mapping
`method, and FIG. 4 and FIG. 5 are diagrams illustrating a
`method for transmitting information, which is mapped in
`accordance with the time-first mapping method as illustrated
`in FIG. 3, in accordance with the SC-FDMA scheme.
`The information sequences to be transmitted to the uplink
`can be arranged temporally in the time-frequency mapper as
`illustrated in FIG. 3. In other words, 12 information data are
`mapped temporally in a first virtual subcarrier region, and
`then subsequent 12 information data are mapped temporally
`in a second virtual subcarrier region.
`After time-frequency mapping is performed as above, the
`sequences arranged on a frequency axis as illustrated in FIG.
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`4 and FIG. 5 undergo DFT and then are inserted to a desired
`frequency band. Afterwards, IFFT and CP insertion are per-
`formed for each frequency region information, which can be
`transmitted as SC-FDMA symbols. FIG. 4 and FIG. 5 illus-
`trate a procedure of generating and transmitting the
`SC-FDMA symbols. FIG. 4 illustrates a case where a normal
`CP is used, and FIG. 5 illustrates a case where an extended CP
`is used.
`
`When data are transmitted to the uplink, the control infor-
`mation can also be transmitted thereto. At this time, the con-
`trol information and the data information are multiplexed
`through rate matching. However, the ACK/NACK informa-
`tion can be transmitted in such a manner that it is overwritten
`
`in bit streams of the data information or symbols where data
`information and control information are multiplexed. In this
`case, “overwritten” means that specific information mapped
`in the resource region is skipped and the corresponding region
`is mapped. Also, “overwritten” means that the length of the
`entire information is maintained equally even after specific
`information is inserted. This overwriting procedure may be
`represented by puncturing.
`Generally, the control information requires higher reliabil-
`ity than the data information. To this end, the control infor-
`mation should be multiplexed or inserted near the reference
`signal. In this case, it is possible to obtain the effect of channel
`estimation performance, thereby expecting improvement of
`performance.
`However, since the ACK/NACK information also requires
`high reliability in a receiver, ifthe general control information
`is arranged near the reference signal, priority between the
`control information and the ACK/NACK signals should be
`considered.
`
`Accordingly, methods for multiplexing data information
`bit streams, control information bit streams, andACK/NACK
`information sequences at different priorities will be described
`as various embodiments of the present invention.
`According to one embodiment ofthe present invention, the
`control information is multiplexed serially with the data
`information, and is mapped with a multiplexing region in
`accordance with the aforementioned time-first mapping
`method. In this case, “multiplexed serially” means that the
`data information is mapped with a sequence corresponding to
`the multiplexed result directly after the control information is
`mapped with the sequence, or vice versa. Also, according to
`one embodiment of the present invention, the ACK/NACK
`signals are arranged to be transmitted through both symbols
`near a symbol through which the reference signal is transmit-
`ted.
`
`FIG. 6 is a diagram illustrating a method for transmitting
`uplink signals in accordance with one embodiment of the
`present invention.
`According to this embodiment, when the control informa-
`tion and the data information are multiplexed, they are seri-
`ally connected with each other so that they are mapped with
`SC-FDMS symbols in accordance with the time-first map-
`ping method and then are transmitted to the uplink. If the
`ACK/NACK information should also be transmitted, among
`the serially multiplexed data, modulation symbols located
`near the reference signal are punctured so that the ACK/
`NACK signals are inserted thereto. In FIG. 6, a reference
`numeral 601 illustrates that the data and control signals are
`multiplexed serially if the ACK/NACK signals are not trans-
`mitted. A reference numeral 602 illustrates that the ACK/
`
`NACK signals are arranged by puncturing the multiplexed
`data if the ACK/NACK signals should be transmitted to the
`uplink. Also, a reference numeral 603 illustrates that infor-
`mation sequences such as the reference numeral 602 are
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`7
`mapped in the time-frequency region in accordance with the
`time-first mapping method. In the reference numeral 603 of
`FIG. 6, it is supposed that the reference signal is transmitted
`through a part between symbol indexes #3 and #4 and a part
`between symbol indexes #9 and #10.
`As can be aware of it from the mapping type illustrated in
`the reference numeral 603 of FIG. 6, after the control signals
`are serially connected with data and then multiplexed, they
`are mapped in the time-frequency region in accordance with
`the time-first mapping method. Also, the ACK/NACK signals
`can be set in such a manner that they are overwritten in the
`data signals multiplexed with two symbols (symbols #3, 4, 9
`and 10 in FIG. 6) at both sides ofthe SC-FDMA symbols to
`which the reference signal is transmitted;
`FIG. 7 and FIG. 8 are diagrams illustrating a method for
`processing a number of ACK/NACK information data to be
`transmitted in accordance with one embodiment of the
`present invention.
`In detail, when the number of ACK/NACK information
`data to be transmitted is more than the number of subcarriers
`(of a Virtual frequency region) to which data are transmitted
`before and after the reference signal, the ACK/NACK infor-
`mation can be transmitted through additional SC-FDMA
`symbols in addition to both symbols nearest to the reference
`signal. In FIG. 7 and FIG. 8, the ACK/NACK information is
`transmitted through additional symbols in the order of the
`symbols near reference symbols in addition to both symbols
`near the reference symbols.
`At this time, the SC-FDMA symbols existing based on the
`reference signal may not be arranged symmetrically depend-
`ing on a structure ofthe SC-FDMA sub-frame ofthe uplink as
`illustrated in FIG. 8. Accordingly, considering this, the ACK/
`NACK information should be inserted by puncturing.
`When the control information is arranged on the time-axis
`in accordance with the aforementioned embodiment of the
`present invention, the control information and the data infor-
`mation are arranged in due order so that they are mapped in
`the resource region. Also, if the ACK/NACK information is
`arranged near the reference signal, the ACK/NACK informa-
`tion can be overwritten in the control information as well as
`the data information.
`FIG. 9 is a diagram illustrating that the ACK/NACK signals
`are inserted by puncturing the control signals as well as the
`data signals in accordance with another embodiment of the
`present invention.
`According to this embodiment, since the ACK/NACK
`information is substantially control information, priority is
`given to control information channels, so that the control
`information channel having the highest priority is arranged
`near the reference signal for protection of channel estimation
`while the control information channels having relatively low
`priority are sequentially mapped on the time axis and then
`transmitted. Particularly, in this embodiment, it is supposed
`that the ACK/NACK information has higher priority than the
`control information. At this time, the control information and
`the data information are sequentially arranged on the time
`axis in accordance with the time-first mapping method and
`then multiplexed. The ACK/NACK information punctures
`the data/control information located near the reference signal.
`In detail, a reference numeral 901 of FIG. 9 illustrates that
`the data and control signals are multiplexed if the ACK/
`NACK signals need not
`to be transmitted. A reference
`numeral 902 of FIG. 9 illustrates that data, control signals and
`ACK/NACK signals are multiplexed if the ACK/NACK sig-
`nals should be transmitted. Also, a reference numeral 903 of
`FIG. 9 illustrates that the multiplexed uplink signals are
`mapped in the time-frequency region as illustrated in the
`reference numeral 902.
`As illustrated in the reference numeral 903 of FIG. 9, it is
`noted from this embodiment that the ACK/NACK signals can
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`puncture the control signals as well as the data matched near
`the reference signal. In this way, if resource mapping is per-
`formed by giving priority to the control signals, good channel
`estimation effect can be obtained as the ACK/NACK infor-
`mation is located near the reference signal. On the other hand,
`since a small number of control signals are punctured by the
`ACK/NACK signals, it may not affect performance. In one
`embodiment shown in FIG. 9, the ACK/NACK signals may
`puncture the control signals/data equally distributed in the
`virtual frequency axis. That is, if the number of virtual sub-
`carriers available for the above puncturing by the ACK/
`NACK signals is “N” and the number of A