WO2012046998A2 - Appareil de transmission et procédé de communication pour celui-ci, et appareil de réception et procédé de communication pour celui-ci - Google Patents

Appareil de transmission et procédé de communication pour celui-ci, et appareil de réception et procédé de communication pour celui-ci Download PDF

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WO2012046998A2
WO2012046998A2 PCT/KR2011/007328 KR2011007328W WO2012046998A2 WO 2012046998 A2 WO2012046998 A2 WO 2012046998A2 KR 2011007328 W KR2011007328 W KR 2011007328W WO 2012046998 A2 WO2012046998 A2 WO 2012046998A2
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combination
vectors
beam selection
selecting
beamforming
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PCT/KR2011/007328
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English (en)
Korean (ko)
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WO2012046998A3 (fr
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박경민
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(주)팬택
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0619—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal using feedback from receiving side
    • H04B7/0621—Feedback content
    • H04B7/0626—Channel coefficients, e.g. channel state information [CSI]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H04B7/0456—Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
    • H04B7/046—Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting taking physical layer constraints into account
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0619—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal using feedback from receiving side
    • H04B7/0636—Feedback format
    • H04B7/0645—Variable feedback
    • H04B7/065—Variable contents, e.g. long-term or short-short
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/02—Arrangements for optimising operational condition
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/10—Polarisation diversity; Directional diversity

Definitions

  • the present specification relates to a wireless communication system, and relates to a wireless communication system using a multiple input multiple output antenna (MIMO) at both a transmitting and receiving end.
  • MIMO multiple input multiple output antenna
  • wireless communication systems such as 3GPP, Long Term Evolution (LTE), and LTE-A (LTE Advanced) are high-speed and large-capacity communication systems that can transmit and receive various data such as video and wireless data beyond voice-oriented services.
  • LTE Long Term Evolution
  • LTE-A LTE Advanced
  • An object of the present invention is to provide a communication method of a transmission device.
  • Another object of the present invention is to provide a transmission apparatus.
  • Another object of the present invention is to provide a communication method of a receiving apparatus.
  • Another object of the present invention is to provide a receiving apparatus.
  • a transmission apparatus including multi-stage precoders for transmitting a signal through two layers, the precoding matrix including four adjacent beamforming vectors for performing beam forming from the receiver A first channel state information indicating one, one of a first beamforming vector and a second beamforming vector of the four beamforming vectors, and a beam selection vector for selecting one of a third beamforming vector and a fourth beamforming vector; One of the combination of beam selection vectors for overlapping selection of the first beamforming vector, the beam selection vector combination for overlapping selection of the third beamforming vector, and the beam for overlapping selection of the second beamforming vector, including combinations; One of the beam selection vector combinations for overlapping selection of the selection vector combination and the fourth beamforming vector, and the first beamforming vector and the second beam.
  • the combinations of the beam selection vector (S a 1, S a channel information receiving step of receiving channel information including second channel state information indicating one of a 2 ); And multi-stage precoding using a first precoding matrix corresponding to the received first channel state information and a second precoding matrix corresponding to the received second channel state information to transmit a signal. It is possible to provide a communication method of the device.
  • Another embodiment includes a layer mapper that maps codewords to two layers; A first channel indicating one of precoding matrices including four adjacent beamforming vectors for beamforming a data symbol mapped to the layer by the layer mapper from a receiver; A beam selection vector including a combination of a first precoding matrix corresponding to the state information and beam selection vectors for selecting one of the first and second and the third and fourth of the four beamforming vectors And one of the combinations of the second and the third beam selection vectors, and one of the combinations of the fourth and the second and the third and the combination of the beam selection vectors.
  • Another embodiment is a wireless communication system in which a transmitter including a multi-stage precoder for transmitting a signal over two layers transmits a signal, the method comprising: receiving a reference signal for estimating a propagation channel from the transmitter; And first channel state information indicating one of the precoding matrices including four adjacent beamforming vectors for performing beam forming, one of the first and second of the four beamforming vectors, and a third one.
  • Combinations of the beam selection vectors S a 1 optionally including one of a combination of selecting a fourth and a combination of beam selection vectors for selecting a first and a second, and a combination for selecting a third and a fourth;
  • S 2 a) of the communication method of a receiving apparatus comprising a transmission step of transmitting the information channel and a second channel state information indicative of the one in the transmitter It can provide.
  • Another embodiment is an antenna array for receiving a reference signal for estimating a propagation channel from a transmitter in a wireless communication system in which a transmitter including a multi-stage precoder transmitting a signal through two layers transmits the signal. ; And
  • First channel state information indicating one of the precoding matrices including four adjacent beamforming vectors for performing beam forming, and one of the first, second, and third and fourth of the four beamforming vectors.
  • Combinations of the beam selection vectors S a 1 , S a optionally including one of a combination of overlapping selections, a combination of beam selection vectors for selecting first and second, and a combination for selecting third and fourth; 2 ) a receiving device including a channel information feedback device for transmitting channel information including second channel state information indicating one of the transmitters to the transmitting device; Can be provided.
  • FIG. 1 is a diagram schematically illustrating a wireless communication system to which embodiments are applied.
  • FIG. 2 illustrates a wireless communication system in which a base station and a terminal exchange channel state information.
  • FIG. 3 is a configuration diagram of each of a base station and a terminal according to an embodiment in a MIMO wireless communication system.
  • FIG. 4 is a flowchart illustrating a communication method of a transmission apparatus according to another embodiment.
  • FIG. 5 is a flowchart illustrating a communication method of a receiving apparatus according to another embodiment.
  • FIG. 1 illustrates a wireless communication system to which embodiments are applied.
  • Wireless communication systems are widely deployed to provide various communication services such as voice and packet data.
  • a wireless communication system includes a user equipment (UE) 10 and a base station 20 (BS).
  • UE user equipment
  • BS base station 20
  • Terminal 10 in the present specification is a generic concept that means a user terminal in wireless communication, WCDMA, UE (User Equipment) in LTE, HSPA, etc., as well as MS (Mobile Station), UT (User Terminal) in GSM ), SS (Subscriber Station), wireless device (wireless device), etc. should be interpreted as including the concept.
  • WCDMA Wideband Code Division Multiple Access
  • UE User Equipment
  • HSPA High Speed Packet Access
  • MS Mobile Station
  • UT User Terminal
  • SS Subscriber Station
  • wireless device wireless device
  • a base station 20 or a cell generally refers to a fixed station communicating with the terminal 10 and includes a Node-B, an evolved Node-B, and a Base Transceiver. May be called other terms such as System, Access Point, Relay Node
  • the terminal 10 and the base station 20 are two transmitting and receiving entities used to implement the technology or the technical idea described in the present specification and are used in a comprehensive sense and are not limited by the terms or words specifically referred to.
  • One embodiment may be applied to asynchronous wireless communication evolving into Long Term Evolution (LTE) and LTE-advanced through GSM, WCDMA, HSPA, and synchronous wireless communication evolving to CDMA, CDMA-2000 and UMB.
  • LTE Long Term Evolution
  • GSM Global System for Mobile communications
  • WCDMA Wideband Code Division Multiple Access
  • HSPA High Speed Packet Access
  • CDMA Code Division Multiple Access-2000
  • UMB Universal Mobile Broadband
  • the wireless communication system to which the embodiments are applied may support uplink and / or downlink HARQ and use channel quality indicator (CQI) for link adaptation.
  • CQI channel quality indicator
  • multiple access schemes for downlink and uplink transmission may be different. For example, downlink uses Orthogonal Frequency Division Multiple Access (OFDMA), and uplink uses Single Carrier-Frequency Division Multiple Access (SC-FDMA). ) Can be used.
  • OFDMA Orthogonal Frequency Division Multiple Access
  • SC-FDMA Single Carrier-Frequency Division Multiple Access
  • a wireless communication system In order to support high-speed information transmission to a user, a wireless communication system considers using a multiple input multiple output (MIMO) technique in which information is transmitted through the same band using an antenna array including multiple antennas. .
  • MIMO multiple input multiple output
  • the MIMO wireless communication system transmits feedback information about a propagation channel or feedback information about a precoder or a precoding matrix (hereinafter referred to as a precoding matrix) suitable for a propagation channel to increase transmission capacity.
  • a precoding matrix a precoding matrix suitable for a propagation channel to increase transmission capacity.
  • an implicit feedback technique that transmits codebook-based channel information or information on a transmission scheme suitable for a channel is a commercial communication system. Is being used by.
  • the precision of reporting on information is closely related to the size of the codebook or the amount of digital factors included in the codebook. This correlation allows the accuracy of the report to be proportional to the feedback overhead.
  • Implicit feedback refers to digital information that is considered to be the most effective for limiting the information to be reported to the transmitter by the finite digital information values and expressing channel information measured in each reporting period.
  • a transmitting device for example, a base station.
  • a set of information consisting of finite digital information values must be designed, and the set of designed digital information is called a codebook.
  • a codebook is designed to represent channel information as finite (N) digital information.
  • N digital values that can represent the channel information most effectively are selected and designed as a codebook.
  • the receiving device compares the digital values registered in the codebook with the measured channel information in each report period, selects a digital value that best represents the measured channel information, and delivers it to the transmitting device.
  • an implicit method is to transmit information about a precoder matrix which is determined to be most suitable for the measured channel. Feedback techniques can be used.
  • a wireless communication system uses a technique of applying a different precoding matrix for each subband, and precoding and Increase the accuracy of the feedback information.
  • the subband precoder matrix is divided into 'broadband portion' and 'subband portion' to reduce the feedback overhead increase caused by subband-specific PMI feedback compared to the conventional technique of reporting one PMI over the entire band.
  • the terminal may report this separately.
  • W W1W2.
  • a wireless communication system according to another embodiment of the present invention may perform dual structure precoding as shown in FIG. 3 in downlink transmission.
  • W1 and W2 constituting the precoding matrix may be transferred from the terminal to the base station through PMI1 or PMI2, which are different precoding matrix indicators.
  • W1 may be a precoding matrix selected for the entire system bandwidth.
  • W2 is selected as one precoder matrix for the entire system bandwidth or one precoder matrix for each subband that is a subset of the system bands. May be selected.
  • the UE may report one W1 and a plurality of W2s within a reporting period, and transmits one digital factor value PMI1 indicating W1 for all bands for which the UE wants to receive a signal.
  • the digital factor values PMI2 determined to be suitable for use as W2 in each subband may be reported to the base station.
  • the reason for using this method is to perform precoding using a different precoder matrix for each subband.
  • W1 and W2 may have a structure as follows.
  • W1 is [V n 0; 0 V n ] block diagonal matrix.
  • W2 is a matrix that performs a co-phasing operation to correct for phase mismatch between antenna groups.
  • W1 reported through PMI1 is a subset containing a total number of beamforming vectors, for example n (n is an integer of 1 or more) out of 32 beamforming vectors.
  • W2 reported through PMI2 selects the beamforming vectors of r out of these n beamforming vectors (r is an integer greater than or equal to 1 less than n) and co-phasing. Do the work. At this time, W2 may repeatedly select the same beamforming vector, and r is a value determined by a transmission rank. The value of n may vary according to the value of rank r to be transmitted.
  • the precoder matrix W1 indicated by the digital index n may be as follows.
  • V n is beam forming vectors that perform beam forming, and may perform beam forming according to a signal transmission and reception direction. Consists of zeros and is Is the same column vector as.
  • adjacent overlapping beams at V n of W1 can be used to reduce the edge effect in frequency selective procoding.
  • the size of V n is 4 will be described as an example.
  • the magnitude of V n is not limited to four.
  • W1 matrices are expressed in terms of the indices of the beams: [0,1,2,3], [2,3,4,5], [4,5,6,7], .. ..., [28,29,30,31], [30,31,0,1].
  • the beams are described as being adjacent, the present invention is not limited thereto, and the W1 matrix may be formed of non-adjacent beams.
  • two beamforming vectors may overlap each other.
  • [2,3] overlaps with [0,1,2,3] and [2,3,4,5].
  • W1 may coincide with the spatial covariance of the dual polarized antenna array (see 428 of FIG. 3) polarized at a constant distance as described with reference to FIG. 3.
  • V n is beam forming vectors that perform beam forming, and may be expressed by Equation 3 below.
  • each element of the codebook for reporting W1 may be composed of a combination of a plurality of beam forming vectors.
  • V 0 32 (1,1,1,1 ⁇
  • V 1 32 ( 1, e j ( ⁇ / 16) , e j (2 ⁇ / 16) , e j (3 ⁇ / 16) ⁇
  • V 2 32 (1, e j (2 ⁇ / 16) , e j (3 ⁇ / 16) , e j (4 ⁇ / 16) ⁇
  • V 31 32 (1, e j (31 ⁇ / 16) , e j (32 ⁇ / 16) , e j (33 ⁇ / 16 ) ⁇
  • W2 simultaneously performs the operation of selecting r of the plurality of beamforming vectors included in W1 k and the co-phasing operation.
  • W2 may be defined as in Equation 6.
  • S a 1 and S a 2 are beam selection vectors for performing beam selection
  • C a is a co-phase element for performing phase matching.
  • S a 1 selects a beamforming vector to be used for the first layer transmission when the value of PMI2 indicating W2 is a from four beamforming vectors selected by W1, and S a 2 represents W2.
  • PMI2 indicating a is a
  • a beamforming vector to be used for the second layer transmission is selected from four beamforming vectors selected by W1.
  • S a 1 and S a 2 may be defined as follows.
  • S a 1 , S a 2 are column vectors of length 4 with one value equal to 1 and the other equal to zero.
  • C a is 1 or It can have a value of.
  • S a 2 [0; 1; 0; 0]
  • C a 1
  • the shape of W2 is represented by Equation 6
  • W2 represented by Equation 8 selects the first beamforming vector among the four beamforming vectors selected by W1 as the beamforming vector to be used for the first layer transmission, and W1 as the beamforming vector to be used for the second layer transmission.
  • the second beamforming vector is selected from the selected four beamforming vectors.
  • the UE examines the precoder matrix or beam forming vector to be used for each subband when reporting the precoder matrix, and N vectors (four according to Equation 4) determined to be most frequently used And define it as broadband part information and report it through PMI1.
  • Equation 5 is an example of a case in which the UE selects four adjacent beamforming vectors when reporting broadband information.
  • the subband portion information is also determined and reported to the base station using PMI2.
  • Equation 8 is an example of a case in which the UE selects two of the four beamforming vectors and performs a co-phasing operation when reporting subband information.
  • a structure of W2 for performing rank2 transmission is presented.
  • W1 selects a subset consisting of four beamforming vectors
  • W2 selects two beamforming vectors from the four beamforming vectors
  • a co-phase element for performing phase matching between two beamforming vectors is selected.
  • the present invention proposes a method of expressing a phase coincidence selection operation of W2 in 3 bits, but expressing all beamforming vectors or precoding matrices in the same manner as in the case of using all 10 beamforming vector selection methods.
  • e 1 is [1; 0; 0; 0] in Equation 6
  • e 2 is [0; 1; 0; 0]
  • e 3 is [0; 0; 1; 0]
  • e 4 may represent [0; 0; 0; 1].
  • a codebook or a combination of beam selection vectors representing PMI2 reporting W2 in three bits may be designed.
  • V 0 and V 2 are used simultaneously, V 2 and V 4 are used simultaneously.
  • V 2n can not be selected for the V 2n + 1 coexistence including four beamforming vectors of the first and third beamforming vector constituting W1. As a result, the resolution of the precoding that can be expressed through the combination of W1 and W2 is reduced.
  • W1 By using the superposition feature of W1, it is possible to express all combinations of four adjacent beamforming vectors without using all 10 combinations of W2 beam selection vectors.
  • the combination rule of the beam selection vector for expressing the adjacent four beamforming vector combinations by the 3-bit W2 beam selection is as follows.
  • next vector set can be represented by only one PMI1 value or only one W1.
  • (S a 1 , S a 2 ) should be selected to represent the above combination. That is, the following (S a 1 , S a 2 ) must be set. In other words, combinations of beam selection vectors for selecting one of the first and second of the beamforming vectors constituting W1 and the other of the third and fourth must be included as essential component combinations.
  • Some elements of the rank 2 configuration consisting of two combinations of four adjacent beamforming vectors may be represented by two PMI1 values or two W1.
  • the combination (e 1 , e 1 ) of the beam selection vectors overlappingly selecting the first of the beamforming vectors constituting W1 and the combination (e 3 , e 3 ) overlappingly selecting the third may be selectively included.
  • four adjacent beamforming vectors constituting W1 overlap two beamforming vectors. Specifically, in (e 1, e 1) of four adjacent beamforming vector that (e 3, e 3) to (V 0, V 1, V 2, V 3) overlapping the first to the V 0 of the selected four
  • overlapping selection of the third ones V 0 of the adjacent beamforming vectors V 30 , V 31 , V 0 , V 1 is the same.
  • a combination (e 2 , e 2 ) of beam selection vectors for overlapping the second selection of the beamforming vectors constituting W1 and a combination (e 4 , e 4 ) for overlapping the fourth selection may be selectively included.
  • a combination (e 1 , e 2 ) of beam selection vectors for selecting the first and second of the beamforming vectors constituting W1 and a combination for selecting the third and fourth (e 3 , e 4 ) may be optionally included. .
  • the W2 beam selection is performed using seven combinations or three bits. In this case, all beamforming vector combinations for rank 2 transmission can be expressed.
  • This method proposes a method of setting eight (S a 1 , S a 2 ) combinations with three bits, and the combination of the other beam selection vector is selected from (1) each of the three selection element combinations. Add the most frequently used combination of the remaining three (S a 1 , S a 2 ) combinations, or (2) one of the eight cases that can be represented by 3 bits, or is reserved. One of the three (S a 1 , S a 2 ) combinations may be completed in any manner or a predetermined rule to complete the W2 beam selection.
  • the first case is selected one by one and the remaining three (S a 1 , S a 2 ) combinations, namely (e 3 , e 3 ) and (e 4 , e 4 ), (e 3 , e 4 ) Among the most frequently used combinations can be added.
  • the third case one of the other three combinations of (S a 1 , S a 2 ), namely (e 3 , e 3 ) and (e 4 , e 4 ), (e 3 , e 4 ) To a predetermined rule.
  • the essential combinations (e 1 , e 3 ) and (e 1 , e 4 ), (e 2 , e 3 ), (e 2 , e 4 ) are essentially included and optional combinations, i.e. ( e 1, e 1): ( e 3, e 3) of the (e 1, the e 1), (e 2, e 2) :( e 4, e 4) of the (e 2, e 2), (e 1 , e 2 ): select (e 3 , e 4 ) from (e 3 , e 4 ) and select the remaining three (S a 1 , S a 2 ) combinations, namely (e 3 , e 3 ) Since one of (e 4 , e 4 ) and (e 1 , e 2 ) is added (e 4 , e 4 ), the above combinations can be configured as beam selection vectors.
  • PMI1 when configuring a combination of beam selection vectors, PMI1 may be expressed as follows.
  • n is other than 0 and 1.
  • desired beamforming vectors may be selected using the same principle.
  • Combination of the beam selection vectors possible according to the above rule is shown in Table 1 below only by subscripts of the beam selection vectors.
  • eight (S a 1 , S a 2 ) combinations are set by 3 bits.
  • the combination of the other beam selection vector is selected from (1) three combinations of selection elements, and the remaining three ( S a 1 , S a 2 ) add the most frequently used combination of combinations, or (2) one of the eight cases that can be represented by three bits is reserved without use, or (3) Assume that one of the remaining three (S a 1 , S a 2 ) combinations used any scheme or predetermined rule. .
  • the aforementioned dual structure precoder enables signal transmission through a different beam for each subband when transmitting a signal to each terminal, and also reduces feedback overhead through dual structure feedback. Has an effect.
  • FIG. 2 illustrates a wireless communication system in which a base station and a terminal exchange channel state information.
  • the wireless communication system 100 stores at least one terminal, for example, n terminals 110, in the base station 120 and the base station 120, similarly to the wireless communication system of FIG. 1. It may include.
  • the terminals 110 may be terminals currently connected or attempting additional access, but only one terminal is shown in FIG. 3.
  • the base station 120 includes a multi-stage precoder including at least two first and second precoders as described below.
  • the base station 120 uses the first precoding matrices used for the first precoder and the first pre-coding matrices representing the first indexes indexing them and the second precoding matrices used for the second precoder and these.
  • the second codebook 124 representing the second indexes to be indexed may be stored or generated.
  • the second codebook 124 may store a combination of beam selection vectors, such as Equation 8, or the like. If the second codebook is configured based on the combination of essential elements of Equation 12, it can be expressed as shown in Table 3 below.
  • the second codebook 124 may store 1 or j as C a, which is a co-phase element that performs a phase matching operation. That is, W2 simultaneously performs a task of selecting one of a plurality of beam forming vectors included in W1 n and a co-phasing operation.
  • W1 since W1 includes four beamforming vectors, there may be a total of 10 ways in which W2 selects four beamforming vectors through S a 1 and S a 2 . Therefore, using 4 bits to express 10 beam selections is inefficient, so only 8 out of 10 cases are represented by 3 bits, and the beam selection can express all combinations of four adjacent beamforming vectors.
  • the combinatorial rule of vectors has been described above.
  • the combination of the other beam selection vector is selected from (1) each of the three selection element combinations and the remaining three (S a 1 , S a 2 ) add the most frequently used combination of combinations, or (2) one of eight cases that can be represented with three bits, is reserved without use, or (3) One of the three (S a 1 , S a 2 ) combinations can complete the W2 beam selection in any manner or with a predetermined rule.
  • the sender side base station 120 transmits a reference signal 128, and the receiver side terminal 110 receives the reference signal. (128) can be used to estimate the channel.
  • the terminal 110 may estimate the downlink channel during downlink transmission.
  • the terminal 110 may estimate a channel of each subband.
  • the base station 120 may estimate the uplink channel during uplink transmission.
  • the specific signal or symbol is variously named as a reference signal, a reference symbol, a pilot symbol, etc., but in this specification, the specific signal or symbol is referred to as a reference signal, but is not limited to the term. Do not.
  • the reference signal is not only used for the estimation of the frequency domain channel but may also be used for position estimation, control information transmission / reception, transmission / reception of scheduling information, transmission / reception of feedback information, and the like, which are necessary in a wireless communication process between the terminal and the base station.
  • reference signals in uplink transmission include DM-RS (Demodulation RS) and SRS (Sounding RS).
  • Reference signals in downlink transmission include DM-RS (Demodulation RS), CRS (Cell-specific RS), MBSFN RS, and UE-specific RS.
  • CSI-RS as a reference signal transmitted from a base station in order to acquire channel state information (CSI) of a center cell or neighbor cells in the terminal 20 during downlink transmission.
  • the CSI-RS may be used to report a Channel Quality Indicator (CQI) / Precoder Matrix Index (PMI) / Rank Index (RI).
  • CQI Channel Quality Indicator
  • PMI Precoder Matrix Index
  • RI Rank Index
  • the terminal 110 includes a basic first codebook 112 representing the first precoding matrices used for the first precoder and the first indexes for indexing them, and a second precoding matrices used for the second precoder; A second codebook 114 representing the second indexes indexing them may be stored or generated.
  • the first codebook 112 and the second codebook 114 are the same or the same as the first codebook 122 and the second codebook 124 stored in the base station 120, respectively. Can be generated.
  • the terminal 110 may report / feed back the first channel state information 132 for the first precoding matrix selected from the first codebook 112 to the base station 120.
  • each terminal 110 may determine a second precoding matrix and report / feed back the second channel state information 134 of the second precoding matrix to the base station 120.
  • the second channel state information may include 1 or j as 1 bit, which is a co-phase element C a performing a phase matching operation.
  • the second channel state information may be 4 bits in total, 3 bits may represent a combination of beam selection vectors, and the remaining 1 bit may represent C a , which is a co-phase element.
  • the base station 120 receives the first channel state information and the second channel state information from the terminal 110 and then transmits each layer when the rank 2 is transmitted by the first channel state information and the second channel state information in the reverse order as described above. Beamforming vectors and beam selection vectors for may be determined.
  • the second channel state information may include, as one bit, C a (1 or j), which is a co-phase element performing a phase matching operation.
  • the second channel state information may be 4 bits in total, 3 bits may represent a combination of beam selection vectors, and the remaining 1 bit may represent C a , which is a co-phase element.
  • the base station 120 uses the channel state information 132 and 134 reported from each terminal 110 as a basis for the first precoder and the second precoder in the first codebook 122 and the second codebook 124. Determine the precoding matrices of and precode the data symbols using the precoding matrices.
  • the base station 120 transmits the precoded signal to the terminal 110.
  • the terminal 110 decodes the original data after receiving the signal.
  • FIG. 3 is a configuration diagram of each of a base station and a terminal according to an embodiment in a MIMO wireless communication system.
  • the MIMO wireless communication system may include a terminal 410 and a base station 420.
  • the terminal 410 and the base station 420 perform a process of exchanging channel state information between the base station and the terminal in the wireless communication system described with reference to FIG. 2.
  • the terminal 410 is an antenna array 411 for receiving a signal through a downlink channel and a post-decoder 412 for processing the received signal and decoding the original data symbol using a precoding matrix. And an information feedback device 414.
  • Antenna array 411 may use multiple antennas.
  • the antenna array 411 may form a polarized antenna array.
  • an array may be implemented using a dual polarized antenna array in which two antennas having different polarizations are alternately installed.
  • the post decoder 412 corresponds to the first precoder 422 and the second precoder 424 of the base station 420.
  • the post decoder 412 transmits the received reference signal to the channel information feedback device 414.
  • the channel information feedback device 414 may receive the reference signal and estimate the channel using the reference signal.
  • the channel information feedback device 414 may generate channel information including the first channel state information and the second channel state information described with reference to FIG. 2.
  • the channel information feedback device 414 may feed back this channel information to the base station 420.
  • the channel information feedback device 414 may store the second codebook 114 in the form of Equation 8 or store combinations of beam selection vectors such as Equation 10.
  • W2 simultaneously performs a task of selecting one of a plurality of beam forming vectors included in W1 n and a co-phasing operation.
  • the second codebook 124 may store 1 or j as C a, which is a co-phase element performing a co-phasing operation.
  • the channel information feedback device 414 may report / feed back the first channel state information 132 for the first precoding matrix selected from the first codebook 112 to the base station 120.
  • the channel information feedback apparatus 414 may determine the second precoding matrix and report / feed back the second channel state information 134 for the second precoding matrix to the base station 120.
  • the second channel state information may include, as one bit, C a (1 or j), which is a co-phase element performing a phase matching operation.
  • the second channel state information may be 4 bits in total, 3 bits may represent a combination of beam selection vectors, and the remaining 1 bit may represent C a , which is a co-phase element.
  • the base station 420 includes a layer mapper 421 that maps codewords to a layer, and a precoder 425 that includes precoding the layer mapped data symbols using a precoding matrix.
  • antenna array 428 for transmitting in air.
  • the precoder 425 may include a first precoder 422 and a second precoder 424 for precoding data symbols. In this case, the first precoder 422 and the second precoder 424 may precode the data symbols by their first precoding matrix and the second precoding matrix, respectively.
  • a characteristic of the precoder having the dual structure shown in FIG. 3 is that when the terminal reports channel state information for W1 and W2, the frequency bands to which W1 and W2 respectively correspond are different.
  • Antenna array 428 of base station 420 may use multiple antennas.
  • the antenna array 428 may form a polarized antenna array.
  • an array may be implemented using a dual polarized antenna array in which two antennas having different polarizations are alternately installed.
  • the antenna arrays 411 and 428 are exemplarily described as using a dual polarized antenna array, but the present invention is not limited thereto.
  • the base station 420 may report / feedback the first channel state information and the second channel state information from the channel information feedback device 414 of the terminal 410 through the antenna array 428.
  • the base station 420 determines precoding matrices of the first precoder 422 and the second precoder 424 in the first codebook and the second codebook based on the channel state information reported from each terminal 410.
  • the precoding matrices are used to precode the data symbols.
  • the feedback period or the interval between the first channel state information and the second channel state information may be different.
  • the first channel state information may be fed back to the base station 420 in a short feedback period / short term
  • the second channel information may be fed back to the base station 420 in a long feedback period / long term.
  • the long feedback period / long term and the short feedback period / short term mean relative to each other
  • the long feedback period / long term means a longer period than the short feedback period / short term.
  • the MIMO wireless communication system for transmitting and receiving codebook restriction information and channel ecological information has been described above.
  • a communication method of a transmission apparatus according to another embodiment will be described.
  • FIG. 4 is a flowchart illustrating a communication method of a transmission apparatus according to another embodiment.
  • a communication method 600 of a transmitter includes a reference signal transmission step (S610) of transmitting a reference signal for estimating a propagation channel to a terminal, and first channel state information from the terminal.
  • Channel information receiving step (S620) for receiving the channel information including the second channel state information it may include a transmission step (S630) for propagating a precoded symbol or signal through the two or more antennas to the air.
  • the transmitting step 630 may include a layer mapping step S632 of mapping a codeword to a layer, a precoding step S634 of precoding symbols, and a transmission step of propagating precoded symbols through the two or more antennas to the air (S636). ) May be included.
  • FIG. 5 is a flowchart illustrating a communication method of a receiving apparatus according to another embodiment.
  • a reference signal receiving step S710 and a channel information transmitting step of transmitting first channel state information and second channel state information to a transmitting device (S720).
  • the terminal 10 may determine a first precoding matrix and report / feed back the first channel state information 132 to the base station 120.
  • each terminal 110 may determine a second precoding matrix and report / feed back the second channel state information 134 of the second precoding matrix to the base station 120.
  • Embodiments as described above may be applied to uplink / downlink MIMO systems, as well as a single cell environment, as well as a coordinated multi-point transmission / reception system (CoMP) and heterogeneous networks. It may be applied to all uplink / downlink MIMO systems.
  • CoMP coordinated multi-point transmission / reception system
  • Ranks 1 and 3 through 8 may apply in the same manner or system.
  • a dual polarization antenna array has been described as an example, but the present invention is not limited thereto.
  • it may be a multi-polarized antenna array, such as a triple polarized wave or quadrupole antenna array.
  • the present invention is not limited to the polarized antenna array but may be applicable to a general antenna array.

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  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Radio Transmission System (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Selon certains modes de réalisation, la présente invention porte sur un système de communication sans fil, plus particulièrement sur un système de communication sans fil qui utilise des antennes multi-entrées multi-sorties (MIMO) sur à la fois l'extrémité de transmission et l'extrémité de réception.
PCT/KR2011/007328 2010-10-08 2011-10-04 Appareil de transmission et procédé de communication pour celui-ci, et appareil de réception et procédé de communication pour celui-ci WO2012046998A2 (fr)

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KR1020100098513A KR20120036698A (ko) 2010-10-08 2010-10-08 송신장치 및 그 통신방법, 수신장치, 그 통신방법
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KR102182168B1 (ko) * 2013-05-07 2020-11-24 엘지전자 주식회사 무선 통신 시스템에서 3 차원 빔포밍을 위한 채널 상태 정보 보고 방법 및 이를 위한 장치
WO2017014609A1 (fr) * 2015-07-23 2017-01-26 엘지전자(주) Procédé d'émission et de réception de signal à base de livre de codes dans un système de communication sans fil à antennes multiples et appareil associé
WO2017014611A1 (fr) * 2015-07-23 2017-01-26 엘지전자(주) Procédé d'émission et de réception de signal à base de livre de codes dans un système de communication sans fil à antennes multiples et appareil associé

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080170523A1 (en) * 2007-01-12 2008-07-17 Samsung Electronics Co., Ltd. Method and apparatus for feedback information transmitting/receiving in mobile telecommunication using multiple input multiple output
US20090046569A1 (en) * 2007-08-14 2009-02-19 Texas Instruments Incorporated Precoding matrix feedback processes, circuits and systems
WO2009096708A1 (fr) * 2008-01-30 2009-08-06 Lg Electronics Inc. Procédé de transmission d'informations de précodage dans un système à plusieurs antennes
US20100002598A1 (en) * 2008-07-02 2010-01-07 Interdigital Patent Holdings, Inc. Method and apparatus for measuring and reporting a rank and a precoding matrix for multiple-input multiple-output communication

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080170523A1 (en) * 2007-01-12 2008-07-17 Samsung Electronics Co., Ltd. Method and apparatus for feedback information transmitting/receiving in mobile telecommunication using multiple input multiple output
US20090046569A1 (en) * 2007-08-14 2009-02-19 Texas Instruments Incorporated Precoding matrix feedback processes, circuits and systems
WO2009096708A1 (fr) * 2008-01-30 2009-08-06 Lg Electronics Inc. Procédé de transmission d'informations de précodage dans un système à plusieurs antennes
US20100002598A1 (en) * 2008-07-02 2010-01-07 Interdigital Patent Holdings, Inc. Method and apparatus for measuring and reporting a rank and a precoding matrix for multiple-input multiple-output communication

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