JP2009526486A - Method and apparatus for performing uplink transmission in a multiple input multiple output single carrier frequency division multiple access system - Google Patents

Abstract

  A method and apparatus for performing uplink transmission in a multiple input multiple output (MIMO) single carrier frequency division multiple access (SC-FDMA) system is disclosed. At a wireless transmit / receive unit (WTRU), input data is encoded and parsed as multiple data streams. After modulation and Fourier transform, one of transmit beamforming, space time coding (STC), and spatial multiplexing is selectively performed based on the channel state information. The symbols are then mapped to subcarriers and transmitted via the antenna. The STC may be space frequency block coding (SFBC) or space time block coding (STBC). Based on the channel state information, rate control for each antenna can be performed for each data stream. In Node-B, MIMO decoding can be performed based on one of minimum mean square error (MMSE) decoding, MMSE continuous interference cancellation (SIC) decoding, and maximum likelihood (ML) decoding. . If STC is implemented at the WTRU, space time decoding may be performed.

Description

  The present invention relates to wireless communication systems. More particularly, the present invention relates to a method and apparatus for implementing uplink transmission in a multiple input multiple output (MIMO) single carrier frequency division multiple access (SC-FDMA) system.

  Developers of third generation (3G) wireless communication systems have developed a new radio access network, high data rate, low latency, packet optimized improvements with higher capacity and better coverage In order to provide a type system, the long-term evolution (LTE) of the 3G system is considered. In order to achieve these goals, instead of using code division multiple access (CDMA) currently used in 3G systems, SC-FDMA is proposed as an air interface for implementing uplink transmission in LTE.

  The basic uplink transmission scheme in LTE is based on low peak-to-average power ratio (PAPR) SC-FDMA transmission with a cyclic prefix and achieves uplink user-to-user orthogonality. Enables efficient frequency domain equalization on the receiver side. Both local and distributed transmissions can be used to support both frequency adaptive transmission and frequency diversity transmission.

  FIG. 1 shows a conventional subframe structure implementing uplink transmission as proposed in LTE. The subframe includes six long blocks (LB) 1 to 6 and two short blocks (SB) 1 and 2. SB 1 and 2 are used for reference signals (ie pilots), coherent demodulation, and / or control or data transmission. LB1-6 are used for control and / or data transmission. The minimum uplink transmission time interval (TTI) is equal to the duration of the subframe. Multiple subframes or time slots can be concatenated as a longer uplink TTI.

  MIMO refers to a type of wireless transmission and reception scheme in which both the transmitter and the receiver utilize multiple antennas. A MIMO system utilizes spatial diversity or spatial multiplexing (SM) to improve signal to noise ratio (SNR) and increase throughput. MIMO has many advantages, including improved spectral efficiency, improved bit rate and robustness at the cell edge, reduced inter-cell and intra-cell interference, improved system capacity, and reduced average transmit power requirements.

  The present invention relates to a method and apparatus for performing uplink transmission in a MIMO SC-FDMA system. At a wireless transmit / receive unit (WTRU), input data is encoded and parsed as multiple data streams. After the modulation and Fourier transform are performed, one of transmit beamforming, precoding, space time coding (STC), and SM is selectively performed based on the channel state information. The symbols are then mapped to subcarriers and transmitted via multiple antennas. The STC may be space frequency block coding (SFBC) or space time block coding (STBC). Based on the channel state information, per antenna rate control may be performed on each data stream. In Node-B, a minimum mean square error (MMSE) decoding, MMSE-successive interference cancellation (SIC) decoding, maximum likelihood (ML) decoding, or similar advanced receiver for MIMO MIMO decoding can be performed based on the technique. If STC is implemented at the WTRU, space time decoding may be performed.

  A more detailed understanding of the present invention can be obtained from the following description of preferred embodiments, given by way of example and to be understood in conjunction with the accompanying drawings, in which:

  As referred to below, the term “WTRU” includes, but is not limited to, user equipment (UE), mobile station, fixed or mobile subscriber unit, pager, mobile phone, personal digital assistant (PDA), computer, or wireless Includes any other type of user equipment that can operate in the environment. As referred to below, the term “Node-B” includes, but is not limited to, a base station, site controller, access point (AP), or any other type of interfacing device in a wireless environment.

  The functionality of the present invention can be incorporated into an integrated circuit (IC) or can be configured as a circuit with multiple interconnect components.

  The present invention provides a method for selectively performing STC, SM, or transmit beamforming for uplink transmission in a MIMO SC-FDMA system. In STC, use any form of STC including STBC, SFBC, quasi-orthogonal Alamouti for four transmit antennas, time reversal STBC (TR-STBC), cyclic delay diversity (CDD), etc. Can do. Hereinafter, the present invention will be described with reference to STBC and SFBC as representative examples of the STC method. SFBC has high resiliency for channels with high time selectivity and low frequency selectivity, and STBC can be used when time selectivity is low. Since the benefit of STC versus transmit beamforming depends on channel conditions (eg, signal-to-noise ratio (SNR)), the mode of transmission (STC vs. transmit beamforming) is based on the appropriate channel metric. Selected.

  FIG. 2 is a block diagram of a WTRU 200 configured in accordance with the present invention. The WTRU 200 includes a channel encoder 202, a rate matching unit 204, a spatial parser 206, a plurality of interleavers 208a to 208n, a plurality of constellation mapping units 210a to 201n, and a plurality of fast Fourier transform (FFT) units 212a to 212a. 212n, multiple multiplexers 218a-218n, spatial transform unit 222, subcarrier mapping unit 224, multiple inverse fast Fourier transform (IFFT) units 226a-226n, multiple CP insertion units 228a-228n, and multiple antennas 230a-230n including. The configurations of WTRUs 200, 500 and Node-B 400, 600 of FIGS. 2 and 4-6 are given by way of example and not limitation, and processing can be performed with more or fewer components. Note that the order can be exchanged.

  The channel encoder 202 encodes the input data 201. Adaptive modulation and coding (AMC) is used, and any coding rate and any coding scheme can be used. For example, the coding rate may be 1/2, 1/3, 1/5, 3/4, 5/6, 8/9, and the like. The coding scheme may be Turbo coding, convolutional coding, block coding, low density parity check (LDPC) coding, or the like. The encoded data 203 can be punctured by the rate matching unit 204. Alternatively, multiple input data streams can be encoded and corrupted with multiple channel encoders and rate matching units.

  The encoded data after rate matching 205 is parsed as a plurality of data streams 207 a-207 n by the spatial parser 206. The data bits on each data stream 207a-207n are preferably interleaved by interleavers 208a-208n. Next, the interleaved data bits 209a to 209n are mapped to the symbols 211a to 211n by the constellation mapping units 210a to 210n according to the selected modulation scheme. The modulation scheme may be binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), 8-phase shift keying (8PSK), 16 quadrature amplitude modulation (QAM), 64QAM, or a similar modulation scheme. Symbols 211a-211n on each data stream are processed by FFT units 212a-212n, which output frequency domain data 213a-213n. Control data 214a-214n and / or pilots 216a-216n are multiplexed with frequency domain data 213a-213n by multiplexers 218a-218n. The frequency domain data 219a-219n (including multiplexed control data 214a-214n and / or pilots 216a-216n) is processed by the spatial transform unit 222.

  Spatial transform unit 222 selectively performs one of transmit beamforming, precoding, STC, SM, or any combination thereof on frequency domain data 213a-213n based on channel state information 220. . Channel state information 220 may include a channel impulse response or precoding matrix, and may include signal to noise ratio (SNR), WTRU rate, channel matrix rank, channel condition number, delay spread, or short and / or long term channel statistics. At least one of them can also be included. The condition number is related to the rank of the channel. An ill-conditioned channel may have no rank. Low rank channels or ill-conditioned channels show better robustness when using diversity schemes such as STBC, since the channels do not have enough flexibility to support SM in transmit beamforming. High rank channels support higher data rates when using SM in transmit beamforming. For low WTRU rates, closed loop precoding or transmit beamforming can be selected, and for high WTRU rates, open loop SM or transmit diversity schemes (such as STC) can be selected. When the SNR is high, closed loop transmit beamforming can be selected, and at low SNR, a transmit diversity scheme may be preferred. Channel state information 220 may be obtained from Node-B using conventional techniques such as direct channel feedback (DCFB).

  Transmit beamforming may be performed using channel matrix decomposition methods (eg, singular value decomposition (SVD)), codebook and index-based precoding methods, SM methods, and the like. For example, in precoding or transmit beamforming using SVD, the channel matrix is estimated and decomposed using SVD, and the resulting right singular vector or quantized right singular vector is the precoding matrix or beam. Used for formation vector. For precoding or transmit beamforming using codebook and index-based methods, the precoding matrix in the codebook with the highest SNR is selected and the index for this precoding matrix is fed back. Metrics other than SNR, such as mean square error (MSE), channel capacity, bit error rate (BER), block error rate (BLER), and throughput can be used as selection criteria. In SM, an identity matrix is used as the precoding matrix (ie, SM does not actually apply precoding weights to antennas). SM is transparently supported by the transmit beamforming architecture (no need for precoding matrix or beamforming vector feedback). The transmit beamforming approach approaches the Shannon boundary with high SNR for low complexity MMSE detectors. For transmission processing at the WTRU 200, transmit beamforming minimizes the required transmit power at the expense of small additional feedback.

  The symbol streams 223a-223n processed by the spatial transform unit 222 are then mapped to subcarriers by the subcarrier mapping unit 224. The subcarrier mapping may be a distributed subcarrier mapping or a local subcarrier mapping. Next, post-subcarrier mapping data 225a to 225n is processed by IFFT units 226a to 226n, and IFFT units 226a to 226n output time domain data 227a to 227n. The CP is added to the time domain data 227a to 227n by the CP insertion units 228a to 228n. The time domain data with CPs 229a-229n is then transmitted via antennas 230a-230n.

  The WTRU 200 supports both a single stream with a single codeword (eg, for SFBC) and one or more streams or codewords with transmit beamforming. A codeword can be viewed as a data stream that is independently channel coded with an independent cyclic redundancy check (CRC). Different codewords can use the same time-frequency code resource.

FIG. 3 shows a transmission processing label according to the present invention. In transmit beamforming, the channel matrix is decomposed using a singular value decomposition (SVD) or equivalent method as follows.
H = UDV ^H formula (1)

The spatial transformation for SM or transmit beamforming can be expressed as:
x = Ts Formula (2)
In the above equation, the matrix T is a generalized transformation matrix. If transmit beamforming is used, the transformation matrix T is chosen to be the beamforming matrix V obtained from the SVD operation described above (ie T = V).

  If STC (ie SPEC or STBC) is used, the coded data for SFBC or STBC can be expressed as:

However, the first column and the second column of the above matrix represent the encoded data related to the antennas 1 and 2, respectively, after SFBC or STBC encoding using the Alamouti method. When SFBC is used, d _2n and d _{2n + 1} represent subcarriers 2n and 2n + 1 data symbols for a pair of subcarriers. When STBC is used, d _2n and d _{2n + 1} represent two adjacent OFDM symbols 2n and 2n + 1. Both schemes have the same effective code rate.

  FIG. 4 is a block diagram of Node-B 400 configured in accordance with the present invention. Node-B 400 includes a plurality of antennas 402a to 402n, a plurality of CP removal units 404a to 404n, a plurality of FFT units 406a to 406n, a channel estimator 408, a subcarrier demapping unit 410, a MIMO decoder 412, a space time decoder ( STD) 414, a plurality of IFFT units 416a to 416n, a plurality of demodulators 418a to 418n, a plurality of deinterleavers 420a to 420n, a spatial deparser 422, a derate matching unit 424, and a decoder 426.

  CP removing units 404a to 404n remove CPs from each of data streams 403a to 403n received from receiving antennas 402a to 402n, respectively. Received data streams 405a to 405n after CP removal are converted into frequency domain data 407a to 407n by FFT units 406a to 406n. Channel estimator 408 generates channel estimate 409 from frequency domain data 407a-407n using conventional methods. Channel estimation is performed for each subcarrier. Subcarrier demapping unit 410 performs the inverse operation that is performed in WTRU 200 of FIG. Next, post-subcarrier demapped data 411 a to 411 n is processed by the MIMO decoder 412.

  MIMO decoder 412 may be a minimum mean square error (MMSE) decoder, an MMSE continuous interference cancellation (SIC) decoder, a maximum likelihood (ML) decoder, or a decoder that uses any other advanced technique for MIMO. MIMO decoding using a linear MMSE (LMMSE) decoder can be expressed as:

_Where R is a receive processing matrix, R _ss and R _vv are correlation matrices,

Is an effective channel matrix that includes the effect of the V matrix on the estimated channel response.

  If STC is used in WTRU 200, STD 414 decodes the STC. SFBC or STBC decoding using MMSE can be expressed as follows:

Where H is the estimated channel matrix.

A channel coefficient h _ij in the channel matrix H is a channel response corresponding to the transmitting antenna j and the receiving antenna i.

  STC is advantageous over transmit beamforming at low SNR. Specifically, simulation results demonstrate the advantage of using STC with low SNR over transmit beamforming. The STC does not require channel state information feedback and is simple to implement. STBC is robust to channels with high frequency selectivity, and SFBC is robust to channels with high time selectivity. It may be advantageous when SFBC can be decoded as a single symbol and low latency is required (eg, voice over IP (VoIP)). Under quasi-static conditions, both SFBC and STBC give similar performance.

  After MIMO decoding (when STC is not used) or after space-time decoding (when STC is used), the decoded data 413a-413n or 415a-415n is converted into time domain data 417a-417n. Processed by IFFT units 416a-416n. Time domain data 417a-417n is processed by demodulators 418a-418n to generate bitstreams 419a-419n. Bitstreams 419a-419n are processed by deinterleavers 420a-420n, which are the inverse operations of interleavers 208a-208n of WTRU 200 in FIG. The deinterleaved bitstreams 421a to 421n are merged by the spatial deparser 422. The merged bitstream 423 is then processed by the derate matching unit 424 and the decoder 426 to recover the data 427.

  Transmit beamforming at the WTRU 200 requires CSI to calculate the precoding matrix V. Node-B 400, 600 includes a channel state feedback unit (not shown) for sending channel state information to the WTRU. The feedback requirements for multiple antennas increase with the product of the number of transmit and receive antennas as well as delay spread, but the capacity only increases linearly. Thus, limited feedback can be used to reduce feedback requirements. The most direct method for limited feedback is channel vector quantization (VQ). A vectorized codebook can be constructed using interpolation methods. Calculation of the V matrix requires eigen-decomposition. In matrix-based precoding methods, feedback or quantization can be used. In the matrix-based precoding method, the best precoding matrix in the codebook is selected and the index for the selected precoding matrix is fed back. The best precoding matrix is determined based on predetermined selection criteria such as maximum SNR, best correlation, or any other suitable metric. Quantized precoding can be used to reduce the computational requirements of the WTRU.

  Whether the eigen decomposition required to obtain the V matrix is implemented at the WTRU 200, at the Node-B 400, or both, information about CSI is still needed at the WTRU 200. If eigendecomposition is performed at Node-B 400, CSI may be used at WTRU 200 to further improve the estimation of the transmit precoding matrix at WTRU 200.

  Robust feedback of the spatial channel can be obtained by averaging over frequency. This method is sometimes called statistical feedback. The statistical feedback may be average feedback or covariance feedback. Since the covariance information is to average over the subcarriers, the feedback parameters for all subcarriers are the same, while the average feedback must be done for each individual subcarrier or group of subcarriers . The latter therefore requires more signaling overhead. Since the channel exhibits statistical correlation for covariance feedback, implicit feedback can be used for transmit beamforming from the WTRU 200. Covariance feedback is also less sensitive to feedback delay compared to per-subcarrier mean feedback.

  5 and 6 are block diagrams of a WTRU 500 and Node-B 600 configured in accordance with another embodiment of the present invention. The WTRU 500 and Node-B 600 implement per-antenna rate control with or without transmit beamforming, precoding, or SM (PARC).

  The WTRU 500 includes a spatial parser 502, a plurality of channel encoders 504a to 504n, a plurality of rate matching units 506a to 506n, a plurality of interleavers 508a to 508n, a plurality of constellation mapping units 510a to 501n, a plurality of FFT units 512a to 512n, A plurality of multiplexers 518a to 518n, a spatial conversion unit 522, a subcarrier mapping unit 524, a plurality of IFFT units 526a to 526n, a plurality of CP insertion units 528a to 528n, and a plurality of antennas 530a to 530n are included. Note that the configuration of the WTRU 500 is given by way of example and not limitation, and that processing can be performed with more or fewer components and the order of processing can be exchanged.

  First, the transmission data 501 is demultiplexed as a plurality of data streams 503 a to 503 n by the spatial parser 502. Adaptive modulation and coding (AMC) may be used for each of the data streams 503a-503n. The bits for each of the data streams 503a-503n are then encoded by each of the channel encoders 504a-504n and destroyed by each of the rate matching units 506a-506n for rate matching. Alternatively, rather than parsing one transmission data as multiple data streams, multiple input data streams may be encoded and corrupted by a channel encoder and rate matching unit.

  Preferably, the encoded data after rate matching 507a-507n is interleaved by interleavers 508a-508n. The data bits after interleaving 509a-509n are then mapped to symbols 511a-511n by constellation mapping units 510a-510n according to the selected modulation scheme. The modulation scheme may be BPSK, QPSK, 8PSK, 16QAM, 64QAM, or a similar modulation scheme. The symbols 511a to 511n on each data stream are processed by the FFT units 512a to 512n, and the FFT units 512a to 512n output the frequency domain data 513a to 513n. Control data 514a-514n and / or pilots 516a-516n are multiplexed with frequency domain data 513a-513n by multiplexers 518a-518n. Frequency domain data 519a-519n (including multiplexing control data 514a-514n and / or pilots 516a-516n) is processed by the spatial transform unit 522.

  Spatial transform unit 522 selectively performs one of transmit beamforming, precoding, STC, SM, or any combination thereof on frequency domain data 513a-513n based on channel state information 520. To do. Channel state information 520 can include a channel impulse response or precoding matrix, and also includes at least one of SNR, WTRU rate, channel matrix rank, channel condition number, delay spread, or short and / or long term channel statistics. be able to. Channel state information 520 can be obtained from Node-B using conventional techniques such as DCFB.

  Transmit beamforming may be performed using channel matrix decomposition methods (eg, SVD), codebook and index-based precoding methods, SM methods, and the like. For example, in precoding or transmit beamforming using SVD, the channel matrix is estimated and decomposed using SVD, and the resulting right singular vector or quantized right singular vector is used for the precoding matrix or beamforming vector. used. For precoding or transmit beamforming using codebook and index-based methods, the precoding matrix in the codebook with the highest SNR is selected and the index for this precoding matrix is fed back. Metrics other than SNR such as MSE, channel capacity, BER, BLER, and throughput can be used as selection criteria. In SM, an identity matrix is used as the precoding matrix (ie, SM does not actually apply precoding weights to antennas). SM is transparently supported by the transmit beamforming architecture (no need for precoding matrix or beamforming vector feedback). The transmit beamforming approach approaches the Shannon boundary with high SNR for low complexity MMSE detectors. For transmission processing at the WTRU 500, transmit beamforming minimizes the required transmit power at the expense of small additional feedback.

  The symbol streams 523a to 523n processed by the spatial transform unit 522 are then mapped to subcarriers by the subcarrier mapping unit 524. The subcarrier mapping may be a distributed subcarrier mapping or a local subcarrier mapping. Next, post-subcarrier mapping data 525a to 525n is processed by IFFT units 526a to 526n, and IFFT units 526a to 526n output time domain data 527a to 527n. The CP is added to each of the time domain data 527a to 527n by the CP insertion units 528a to 528n. Then, time domain data with CPs 529a-529n is transmitted via multiple antennas 530a-530n.

  Node-B 600 includes a plurality of antennas 602a to 602n, a plurality of CP removal units 604a to 604n, a plurality of FFT units 606a to 606n, a channel estimator 608, a subcarrier demapping unit 610, a MIMO decoder 612, an STD 614, and a plurality of IFFTs. Units 616a-616n, a plurality of demodulators 618a-618n, a plurality of deinterleavers 620a-620n, a plurality of derate matching units 622a-622n, a plurality of decoders 624a-624n, and a spatial deparser 626.

  CP removal units 604a-604n remove CPs from each of data streams 603a-603n received from each of receive antennas 602a-602n. Received data streams 605a to 605n after CP removal are converted into frequency domain data 607a to 607n by FFT units 606a to 606n. Channel estimator 608 generates channel estimate 609 from frequency domain data 607a-607n using conventional methods. Channel estimation is performed for each subcarrier. Subcarrier demapping unit 610 performs the inverse operation that is performed in WTRU 500 of FIG. Next, post-subcarrier demapped data 611 a to 611 n is processed by the MIMO decoder 612.

  MIMO decoder 612 may be a MMSE decoder, MMSE-SIC decoder, ML decoder, or a decoder that uses any other advanced technique for MIMO. If STC is used in WTRU 500, STD 614 decodes STC.

  After MIMO decoding (if STC is not used) or space time decoding (if STC is used), the decoded data 613a-613n or 615a-615n is IFFT for conversion to time domain data 617a-617n. Processed by units 616a-616n. Time domain data 617a-617n is processed by demodulators 618a-618n to generate bitstreams 619a-619n. Bitstreams 619a-619n are processed by deinterleavers 620a-620n, which are the inverse operations of interleavers 508a-508n of WTRU 500 in FIG. Each of the deinterleaved bitstreams 621a-621n is then processed by each of the derate matching units 624a-624n. Derate matched bitstreams 623a-623n are decoded by decoders 624a-624n. Decoded bits 625a-625n are merged by spatial deparser 626 and data 627 is recovered.

Embodiment 1. A method for performing uplink transmission in a wireless communication system.

  2. The method of embodiment 1 comprising generating a plurality of encoded data streams.

  3. [0069] 3. The method of embodiment 2 comprising generating a symbol sequence from each encoded data stream according to the selected modulation scheme.

  4). 4. The method of embodiment 3, comprising performing a Fourier transform on each symbol sequence to generate frequency domain data.

  5). 5. The method of embodiment 4 comprising selectively performing one of transmit beamforming, precoding, STC, and spatial multiplexing on the frequency domain data based on the channel state information.

  6). 6. The method of embodiment 5 comprising mapping symbols on each symbol sequence to subcarriers.

  7. 7. The method of embodiment 6 comprising performing inverse Fourier transform on the post-subcarrier mapped data on each symbol sequence to generate time domain data.

  8). 8. The method of embodiment 7, comprising the step of transmitting time domain data.

  9. [0069] 9. The method as in any of the embodiments 5-8, wherein the STC is one of SFBC, STBC, quasi-orthogonal Alamouti coding, TR-STBC, and CDD.

  10. [0069] [0065] The method as in any of the embodiments 5-9, wherein the channel state information is at least one of channel impulse response, precoding matrix, SNR, channel matrix rank, channel condition number, delay spread, WTRU rate, and channel statistics. .

  11. [0069] 11. The method as in any of the embodiments 2-10, further comprising the step of destroying for each encoded data stream for rate matching.

  12 [0069] 12. The method as in any of the embodiments 2-11, further comprising interleaving bits on each encoded data stream.

  13. [0069] 13. The method as in any of the embodiments 5-12, wherein per-antenna rate control is performed on the encoded data stream based on channel state information.

  14 [0069] 14. The method as in any of the embodiments 5-13, wherein the transmit beamforming is transmit eigenbeamforming using channel matrix decomposition.

  15. 14. The method as in any of the embodiments 5-13, wherein transmit beamforming is performed using a codebook and index-based precoding.

  16. [0069] 14. The method as in any of the embodiments 5-13, wherein transmit beamforming is performed using steering vector based beamforming.

  17. 17. The method as in any of the embodiments 4-16, further comprising the step of multiplexing the control data and pilot with frequency domain data.

  18. [0069] 18. The method as in any of the embodiments 1-17, wherein the wireless communication system is a MIMO SC-FDMA system.

  19. [0069] 19. The method as in any of the embodiments 8-18, further comprising receiving time domain data.

  20. 20. The method of embodiment 19 comprising the step of performing a Fourier transform on the received time domain data to generate received frequency domain data.

  21. 21. The method of embodiment 20, comprising performing subcarrier demapping.

  22. 22. The method of embodiment 21 comprising generating a channel estimate.

  23. The method of embodiment 22 comprising performing decoding on the post-subcarrier demapped data based on channel estimation.

  24. 24. The method of embodiment 23, comprising performing an inverse Fourier transform on the decoded received subcarrier demapped data.

  25. 25. The method of embodiment 24 comprising performing demodulation and decoding.

  26. 26. The method as in any of the embodiments 23-25, wherein the decoding is performed based on one of MMSE decoding, MMSE-SIC decoding, and ML decoding.

  27. 27. The method as in any of the embodiments 23-26, further comprising performing space time decoding when space time coding is performed for transmission.

  28. 28. The method as in any of the embodiments 22-27, wherein channel state information is fed back from a communication peer.

  29. 29. The method of embodiment 28, wherein limited feedback is used for channel state information feedback.

  30. 29. The method of embodiment 28 wherein the channel VQ is used for channel state information feedback.

  31. 29. The method of embodiment 28, wherein eigendecomposition of the channel matrix is performed at the communication peer and the V matrix is fed back.

  32. 29. The method of embodiment 28, wherein statistical feedback is used for channel state information feedback.

  33. 33. The method of embodiment 32, wherein for channel state information feedback, one of average feedback and covariance feedback is used.

  34. A WTRU that performs uplink transmission in a MIMO SC-FDMA wireless communication system.

  35. 35. The WTRU of embodiment 34 comprising an encoder that encodes input data.

  36. 36. The WTRU of embodiment 35 comprising a constellation mapping unit that generates a symbol sequence from each encoded data stream according to a selected modulation scheme.

  37. 37. The WTRU of embodiment 36 comprising a Fourier transform unit that performs a Fourier transform on each symbol sequence to generate frequency domain data.

  38. 38. The WTRU of embodiment 37 comprising a spatial transform unit that selectively performs one of transmit beamforming, precoding, STC, and spatial multiplexing on frequency domain data based on channel state information.

  39. 39. The WTRU of embodiment 38 comprising a subcarrier mapping unit that maps the output of the spatial transform unit to a subcarrier.

  40. 40. The WTRU of embodiment 39 comprising an inverse Fourier transform unit that performs inverse Fourier transform on the post-subcarrier mapped data to generate time domain data.

  41. 41. The WTRU of embodiment 40 comprising a plurality of antennas for transmitting time domain data.

  42. [00102] 42. The WTRU as in any of the embodiments 38-41, wherein the spatial transform unit is configured to implement one of SFBC, STBC, quasi-orthogonal Alamouti coding, TR-STBC, and CDD.

  43. 43. The WTRU as in any one of embodiments 38-42, wherein the channel state information is at least one of channel impulse response, precoding matrix, SNR, channel matrix rank, channel condition number, delay spread, WTRU rate, and channel statistics. .

  44. [00102] 44. The WTRU as in any of the embodiments 35-43, further comprising a spatial parser that generates a plurality of encoded data streams from the encoded input data.

  45. 45. The WTRU as in any of the embodiments 35-44, further comprising a spatial parser that generates a plurality of input data streams, wherein each input data stream is encoded with an encoder.

  46. [00102] 46. The WTRU as in any of the embodiments 35-45, further comprising a rate matching unit that destroys for each encoded data stream for rate matching.

  47. [00117] 47. The WTRU as in any of the embodiments 35-46, further comprising an interleaver that interleaves bits on each encoded data stream.

  48. [00102] 48. The WTRU as in any of the embodiments 42-47, wherein the spatial transform unit is configured to perform per antenna rate control on the encoded data stream based on the channel state information.

  49. 49. The WTRU as in any of embodiments 42-48, wherein the spatial transform unit is configured to perform transmit beamforming using channel matrix decomposition.

  50. 50. The WTRU as in any one of embodiments 42-49, wherein the spatial transform unit is configured to perform transmit beamforming using codebook and index-based precoding.

  51. [00110] 51. The WTRU as in any of the embodiments 42-50, wherein the spatial transform unit is configured to perform transmit beamforming using steering vector based beamforming.

  52. [00102] 52. The WTRU as in any of the embodiments 37-51, further comprising a multiplexer that multiplexes control data and pilot with frequency domain data.

  53. 53. The WTRU as in any of the embodiments 38-52, wherein the channel state information is obtained from the Node-B.

  54. Node-B supporting uplink transmission in MIMO SC-FDMA wireless communication system.

  55. 55. The Node-B of embodiment 54 comprising a plurality of antennas for receiving data.

  56. 56. The Node-B of embodiment 55 comprising a Fourier transform unit that performs a Fourier transform on each received data to generate frequency domain data.

  57. 57. The Node-B of embodiment 56 comprising a subcarrier demapping unit that performs subcarrier demapping on frequency domain data.

  58. 58. The Node-B as in any of embodiments 54-57, comprising a channel estimator for generating a channel estimate.

  59. 59. Node-B of embodiment 58 comprising a MIMO decoder that performs MIMO decoding on frequency domain data after subcarrier demapping based on channel estimation.

  60. The Node-B of embodiment 59, comprising an inverse Fourier transform unit that performs an inverse Fourier transform on the output from the MIMO decoder to generate time domain data.

  61. The Node-B of embodiment 60 comprising a demodulator that performs demodulation on the time domain data to generate demodulated data.

  62. The Node-B of embodiment 61, comprising a decoder for decoding the demodulated data.

  63. 63. The Node-B as in any of embodiments 59-62, wherein the MIMO decoder is configured to perform MIMO decoding based on one of MMSE decoding, MMSE-SIC decoding, and ML decoding.

  64. 64. The Node-B as in any of the embodiments 59-63, further comprising a space-time decoder that performs space-time decoding.

  65. 65. The Node-B as in any of embodiments 58-64, further comprising a channel state feedback unit that sends channel state information to the WTRU.

  66. Embodiment 65. The Node-B of embodiment 65, wherein limited feedback is used for channel state information feedback.

  67. Embodiment 65. The Node-B of embodiment 65, wherein the channel VQ is used for channel state information feedback.

  68. Embodiment 65. The Node-B of embodiment 65, wherein statistical feedback is used for channel state information feedback.

  69. 69. The Node-B of embodiment 68 wherein one of average feedback and covariance feedback is used for channel state information feedback.

  Although the features and elements of the invention have been described with respect to particular frames, subframes, or time slot formats in a particular combination of preferred embodiments, each feature or element can be independently used without other features and elements of the preferred embodiment. It can be used, or can be used in various combinations with or without other functions and elements of the invention, and can be used for other frames, subframes, and time slot formats. The method provided in the present invention can be implemented as a computer program, software, or firmware tangibly implemented in a computer readable storage medium executed by a general purpose computer or processor. Examples of computer readable storage media include read only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, CD-ROM discs And optical media such as a digital versatile disc (DVD).

  Suitable processors are, for example, general purpose processors, special purpose processors, conventional processors, digital signal processors (DSPs), multiple microprocessors, one or more microprocessors associated with the DSP core, controllers, microcontrollers, application specific Includes integrated circuits (ASICs), field programmable gate array (FPGA) circuits, any integrated circuits, and / or state machines.

  A processor associated with the software may be used to implement a radio frequency transceiver for use in a WTRU, user equipment, terminal, base station, radio network controller, or any host computer. Camera, camcorder module, videophone, speakerphone, vibration device, speaker, microphone, television transceiver, hands-free headset, keyboard, Bluetooth module, frequency modulation (FM) radio unit, liquid crystal display (LCD) display unit, organic Along with modules implemented in hardware and / or software such as light emitting diode (OLED) display units, digital music players, media players, video game player modules, internet browsers, and / or any wireless local area network (WLAN) modules A WTRU may be used.

FIG. 3 is a diagram illustrating a conventional subframe format proposed for SC-FDMA in LTE. FIG. 3 is a block diagram of a WTRU configured in accordance with the present invention. It is a figure which shows the transmission process label by this invention. FIG. 3 is a block diagram of Node-B configured in accordance with the present invention. FIG. 6 is a block diagram of a WTRU configured in accordance with another embodiment of the present invention. FIG. 6 is a block diagram of Node-B configured in accordance with another embodiment of the present invention.

Claims (41)

A method for performing uplink transmission in a wireless communication system, comprising:
Generating a plurality of encoded data streams;
Generating a symbol sequence from each encoded data stream in accordance with the selected modulation scheme;
Performing a Fourier transform on each symbol sequence to generate frequency domain data;
Selectively performing one of transmit beamforming, precoding, space time coding (STC), and spatial multiplexing on the frequency domain data based on channel state information;
Mapping symbols on each symbol sequence to subcarriers;
A method comprising: performing inverse Fourier transform on sub-carrier mapped data on each symbol sequence to generate time domain data; and transmitting time domain data.   The STC is one of space frequency block coding (SFBC), space time block coding (STBC), quasi-orthogonal Alamouti coding, time reversal STBC (TR-STBC), and cyclic delay diversity (CDD). The method of claim 1 wherein:   The channel state information includes at least one of channel impulse response, precoding matrix, signal to noise ratio (SNR), channel matrix rank, channel condition number, delay spread, wireless transmit / receive unit (WTRU) rate, and channel statistics. The method of claim 1, wherein the number is one. The method of claim 1, further comprising: breaking for each encoded data stream for rate matching. The method of claim 1, further comprising: interleaving bits on each encoded data stream.   The method of claim 1, wherein rate control per antenna is performed on the encoded data stream based on the channel state information.   The method of claim 1, wherein the transmit beamforming is transmit eigenbeamforming using channel matrix decomposition.   The method of claim 1, wherein the transmit beamforming is performed using codebook and index-based precoding.   The method of claim 1, wherein the transmit beamforming is performed using steering vector based beamforming. The method of claim 1, further comprising: multiplexing control data and pilot with the frequency domain data.   The method of claim 1, wherein the wireless communication system is a multiple input multiple output (MIMO) single carrier frequency division multiple access (SC-FDMA) system. Receiving the time domain data;
Performing Fourier transform on the received time domain data to generate received frequency domain data;
Performing subcarrier demapping; and
Generating a channel estimate;
Performing decoding on the received subcarrier demapped data based on the channel estimate;
The method of claim 1, further comprising: performing an inverse Fourier transform on the decoded post-subcarrier demapped data, and performing demodulation and decoding.   The decoding is performed based on one of minimum mean square error (MMSE) decoding, MMSE continuous interference cancellation (SIC) decoding, and maximum likelihood (ML) decoding. The method of claim 12. The method of claim 12, further comprising: performing space time decoding if space time coding is performed for transmission.   The method of claim 1, wherein the channel state information is fed back from a communication peer.   The method according to claim 15, characterized in that limited feedback is used for channel state information feedback.   17. The method of claim 16, wherein channel vector quantization (VQ) is used for channel state information feedback.   16. The method of claim 15, wherein eigendecomposition of the channel matrix is performed at the communication peer and the V matrix is fed back.   The method according to claim 15, characterized in that statistical feedback is used for channel state information feedback.   The method of claim 19, wherein for channel state information feedback, one of average feedback and covariance feedback is used. A wireless transmit / receive unit (WTRU) that performs uplink transmission in a multiple input multiple output (MIMO) single carrier frequency division multiple access (SC-FDMA) wireless communication system, comprising:
An encoder that encodes the input data;
A constellation mapping unit that generates a symbol sequence from each encoded data stream according to a selected modulation scheme;
A Fourier transform unit that performs a Fourier transform on each symbol sequence to generate frequency domain data;
A spatial transform unit that selectively performs one of transmit beamforming, precoding, space time coding (STC), and spatial multiplexing on the frequency domain data based on channel state information;
A subcarrier mapping unit for mapping the output of the spatial transform unit to a subcarrier;
An inverse Fourier transform unit that performs inverse Fourier transform on the data after subcarrier mapping to generate time domain data;
A WTRU comprising a plurality of antennas for transmitting the time domain data.   The spatial transform unit performs one of spatial frequency block coding (SFBC), space time block coding (STBC), quasi-orthogonal Alamouti coding, time reversal STBC (TR-STBC), and cyclic delay diversity (CDD). The WTRU of claim 21 configured to perform.   The channel state information is at least one of channel impulse response, precoding matrix, signal to noise ratio (SNR), channel matrix rank, channel condition number, delay spread, wireless transmit / receive unit (WTRU) rate, and channel statistics. 23. The WTRU of claim 21 wherein The WTRU of claim 21 further comprising a spatial parser that generates a plurality of encoded data streams from the encoded input data. The WTRU of claim 21 further comprising a spatial parser for generating a plurality of input data streams, each input data stream being encoded by the encoder. 23. The WTRU of claim 21 further comprising a rate matching unit that destroys for each encoded data stream for rate matching. 24. The WTRU of claim 21 further comprising an interleaver that interleaves bits on each encoded data stream.   The WTRU of claim 21, wherein the spatial transform unit is configured to perform per-antenna rate control on the encoded data stream based on the channel state information.   The WTRU of claim 21 wherein the spatial transform unit is configured to perform the transmit beamforming using channel matrix decomposition.   24. The WTRU of claim 21 wherein the spatial transform unit is configured to perform the transmit beamforming using codebook and index-based precoding.   23. The WTRU of claim 21 wherein the spatial transform unit is configured to perform the transmit beamforming using steering vector based beamforming. The WTRU of claim 21 further comprising a multiplexer that multiplexes control data and pilot with the frequency domain data.   24. The WTRU of claim 21 wherein the channel state information is obtained from Node-B. A Node-B that supports uplink transmission in a multiple input multiple output (MIMO) single carrier frequency division multiple access (SC-FDMA) wireless communication system, comprising:
Multiple antennas to receive data,
A Fourier transform unit that performs Fourier transform on the received data to generate frequency domain data; and
A subcarrier demapping unit that performs subcarrier demapping on the frequency domain data;
A channel estimator that generates a channel estimate;
A MIMO decoder that performs MIMO decoding on the frequency domain data after subcarrier demapping data based on the channel estimation;
An inverse Fourier transform unit that performs an inverse Fourier transform on the output from the MIMO decoder to generate time domain data;
A demodulator that demodulates the time domain data to generate demodulated data;
A Node-B comprising a decoder for decoding the demodulated data.   The MIMO decoder performs the MIMO decoding based on one of minimum mean square error (MMSE) decoding, MMSE continuous interference cancellation (SIC) decoding, and maximum likelihood (ML) decoding. The Node-B according to claim 34, wherein the Node-B is configured as follows. 36. The Node-B of claim 35, further comprising a space-time decoder that performs space-time decoding. 35. The Node-B of claim 34, further comprising a channel state feedback unit that sends channel state information to the WTRU.   38. Node-B according to claim 37, wherein limited feedback is used for channel state information feedback.   39. The Node-B of claim 38, wherein channel vector quantization (VQ) is used for channel state information feedback.   38. The Node-B of claim 37, wherein statistical feedback is used for channel state information feedback.   41. The Node-B of claim 40, wherein one of average feedback and covariance feedback is used for channel state information feedback.

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