Resource allocation for MIMO-OFDM communication systems

    公开(公告)号:US20060039312A1

    公开(公告)日:2006-02-23

    申请号:US11248890

    申请日:2005-10-11

    IPC分类号: H04B7/204

    摘要: Techniques to schedule terminals for data transmission on the downlink and/or uplink in a MIMO-OFDM system based on the spatial and/or frequency “signatures” of the terminals. A scheduler forms one or more sets of terminals for possible (downlink or uplink) data transmission for each of a number of frequency bands. One or more sub-hypotheses may further be formed for each hypothesis, with each sub-hypothesis corresponding to (1) specific assignments of transmit antennas to the terminal(s) in the hypothesis (for the downlink) or (2) a specific order for processing the uplink data transmissions from the terminal(s) (for the uplink). The performance of each sub-hypothesis is then evaluated (e.g., based on one or more performance metrics). One sub-hypothesis is then selected for each frequency band based on the evaluated performance, and the one or more terminals in each selected sub-hypothesis are then scheduled for data transmission on the corresponding frequency band.

    Reduced complexity detection and decoding for a receiver in a communication system
    2.
    发明申请
    Reduced complexity detection and decoding for a receiver in a communication system 有权
    降低通信系统中接收机的复杂度检测和解码

    公开(公告)号:US20070116143A1

    公开(公告)日:2007-05-24

    申请号:US11345976

    申请日:2006-02-01

    IPC分类号: H04L23/02 H04L1/02 H03D1/00

    摘要: Techniques for performing detection and decoding at a receiver are described. In one scheme, the receiver obtains R received symbol streams for M data streams transmitted by a transmitter, performs receiver spatial processing on the received symbols to obtain detected symbols, performs log-likelihood ratio (LLR) computation independently for each of D best data streams, and performs LLR computation jointly for the M−D remaining data streams, where M>D≧1 and M>1. The D best data streams may be selected based on SNR and/or other criteria. In another scheme, the receiver performs LLR computation independently for each of the D best data streams, performs LLR computation jointly for the M−D remaining data streams, and reduces the number of hypotheses to consider for the joint LLR computation by performing a search for candidate hypotheses using list sphere detection, Markov chain Monte Carlo, or some other search technique.

    摘要翻译: 描述在接收机处执行检测和解码的技术。 在一种方案中,接收机获得用于由发射机发送的M个数据流的R个接收符号流,对接收到的符号执行接收机空间处理以获得检测符号,对于每个D个最佳数据流独立地执行对数似然比(LLR)计算 并且为MD剩余数据流共同执行LLR计算,其中M> D> = 1且M> 1。 可以基于SNR和/或其他标准来选择D个最佳数据流。 在另一方案中,接收机对于每个D最佳数据流独立地执行LLR计算,为MD剩余数据流共同执行LLR计算,并且通过执行候选假设的搜索来减少对于联合LLR计算考虑的假设的数量 使用列表球体检测,马尔科夫链蒙特卡罗或其他搜索技术。

    PHASE CORRECTION FOR OFDM AND MIMO TRANSMISSIONS
    3.
    发明申请
    PHASE CORRECTION FOR OFDM AND MIMO TRANSMISSIONS 有权
    OFDM和MIMO传输的相位校正

    公开(公告)号:US20080056305A1

    公开(公告)日:2008-03-06

    申请号:US11751471

    申请日:2007-05-21

    IPC分类号: H04B3/10

    摘要: Techniques for performing phase correction for wireless communication are described. Received pilot symbols and received data symbols may be obtained from an orthogonal frequency division multiplexing (OFDM) and/or multiple-input multiple-output (MIMO) transmission. First phase information is obtained based upon the received pilot symbols. Second phase information is obtained based upon the received data symbols. The phase of the received data symbols is corrected based upon the first and second phase information (directly and/or indirectly). For example, the phase of the received data symbols may be corrected based upon the first phase information, detection may be performed on the phase corrected data symbols to obtain estimated data symbols, the second phase information may be obtained based upon the estimated data symbols, and the phase of the estimated data symbols may be corrected based upon the second phase information. The phase correction may also be performed in other manners.

    摘要翻译: 描述用于执行无线通信的相位校正的技术。 可以从正交频分复用(OFDM)和/或多输入多输出(MIMO)传输中获得接收到的导频符号和接收的数据符号。 基于接收到的导频符号获得第一相位信息。 基于接收到的数据符号获得第二相位信息。 基于第一和第二相位信息(直接和/或间接地)校正接收到的数据符号的相位。 例如,可以基于第一相位信息来校正接收到的数据符号的相位,可以对相位校正数据符号执行检测以获得估计的数据符号,可以基于估计的数据符号获得第二相位信息, 并且可以基于第二相位信息来校正估计数据符号的相位。 相位校正也可以以其他方式进行。

    Multiple-input, multiple-output (MIMO) systems with multiple transmission modes
    4.
    发明申请
    Multiple-input, multiple-output (MIMO) systems with multiple transmission modes 有权
    具有多种传输模式的多输入多输出(MIMO)系统

    公开(公告)号:US20050094598A1

    公开(公告)日:2005-05-05

    申请号:US10985400

    申请日:2004-11-10

    摘要: Techniques to transmit data on a number of transmission channels in a multi-channel communication system using multiple transmission schemes requiring less channel-state information (CSI). These schemes may include a partial-CSI transmission scheme that transmits a single data stream on each transmit antenna selected for use and a “beam-forming” transmission scheme that allocates all transmit power to a single transmission channel having the best performance. Each transmission scheme may provide good or near-optimum performance for a specific range of operating conditions (or operating SNRs). These multiple transmission schemes may then be combined in a piece-wise fashion to form a “multi-mode” transmission scheme that covers the full range of operating conditions supported by the MIMO system. The specific transmission scheme to be used for data transmission at any given moment would then be dependent on the specific operating condition experienced by the system at that moment.

    摘要翻译: 使用需要较少信道状态信息(CSI)的多个传输方案在多信道通信系统中在多个传输信道上传输数据的技术。 这些方案可以包括在被选择使用的每个发射天线上发送单个数据流的部分CSI传输方案以及将所有发射功率分配给具有最佳性能的单个传输信道的“波束形成”传输方案。 每个传输方案可以为特定范围的操作条件(或操作SNR)提供良好或接近最佳的性能。 然后,这些多个传输方案可以以分段方式组合以形成覆盖由MIMO系统支持的全部操作条件的“多模式”传输方案。 在任何给定时刻用于数据传输的具体传输方案将取决于系统在此刻经历的特定操作条件。

    Receiver structures for spatial spreading with space-time or space-frequency transmit diversity
    5.
    发明申请
    Receiver structures for spatial spreading with space-time or space-frequency transmit diversity 有权
    用于空间时空或空间 - 频率发射分集的空间扩展的接收机结构

    公开(公告)号:US20060050770A1

    公开(公告)日:2006-03-09

    申请号:US11042126

    申请日:2005-01-24

    IPC分类号: H04L1/02 H04B1/707

    摘要: A receiving entity obtains received symbols for a data transmission having at least one data symbol stream sent with space-time transmit diversity (STTD). The receiving entity derives an overall channel response matrix in accordance with the STTD encoding scheme used for the data transmission, derives a spatial filter matrix based on the overall channel response matrix, and performs spatial matched filtering on a vector of received symbols for each 2-symbol interval to obtain a vector of detected symbols for the 2-symbol interval. The receiving entity may perform post-processing (e.g., conjugation) on the detected symbols if needed. Alternatively, the receiving entity derives a spatial filter matrix based on an effective channel response matrix, performs spatial matched filtering on the received symbols for each symbol period to obtain detected symbols for that symbol period, and combines multiple estimates obtained for each data symbol sent with STTD.

    摘要翻译: 接收实体获得具有用空时传输分集(STTD)发送的至少一个数据符号流的数据传输的接收符号。 接收实体根据用于数据传输的STTD编码方案导出整体信道响应矩阵,基于整个信道响应矩阵导出空间滤波器矩阵,并且对每个2-信道的接收符号的向量执行空间匹配滤波, 符号间隔以获得用于2符号间隔的检测符号的向量。 如果需要,接收实体可以在检测到的符号上执行后处理(例如,共轭)。 或者,接收实体基于有效信道响应矩阵导出空间滤波器矩阵,对于每个符号周期对接收到的符号执行空间匹配滤波,以获得该符号周期的检测符号,并且将针对每个符号周期发送的每个数据符号获得的多个估计合并 STTD。

    BROADCAST TRANSMISSION WITH SPATIAL SPREADING IN A MULTI-ANTENNA COMMUNICATION SYSTEM
    6.
    发明申请
    BROADCAST TRANSMISSION WITH SPATIAL SPREADING IN A MULTI-ANTENNA COMMUNICATION SYSTEM 有权
    在多天线通信系统中具有空间扩展的广播传输

    公开(公告)号:US20080031372A1

    公开(公告)日:2008-02-07

    申请号:US11870380

    申请日:2007-10-10

    IPC分类号: H04L27/28

    摘要: An access point in a multi-antenna system broadcasts data using spatial spreading to randomize an “effective” channel observed by each user terminal for each block of data symbols broadcast by the access point. At the access point, data is coded, interleaved, and modulated to obtain ND data symbol blocks to be broadcast in NM transmission spans, where ND≧1 and NM>1. The ND data symbol blocks are partitioned into NM data symbol subblocks, one subblock for each transmission span. A steering matrix is selected (e.g., in a deterministic or pseudo-random manner from among a set of L steering matrices) for each subblock. Each data symbol subblock is spatially processed with the steering matrix selected for that subblock to obtain transmit symbols, which are further processed and broadcast via NT transmit antennas and in one transmission span to user terminals within a broadcast coverage area.

    摘要翻译: 多天线系统中的接入点使用空间扩展广播数据,以随机化由接入点广播的每个数据符号块由每个用户终端观察到的“有效”信道。 在接入点,对数据进行编码,交织和调制,以获得要在N N个传输跨度中广播的N个D个数据符号块,其中N < / SUB >> = 1和N&lt; 1&gt; 1。 N N个数据符号块被划分为N个M个数据符号子块,每个传输跨度的一个子块。 对于每个子块,选择导向矩阵(例如,从一组L个导引矩阵中以确定性或伪随机方式)。 利用为该子块选择的导引矩阵来对每个数据符号子块进行空间处理,以获得发射符号,其进一步经由N T T个发射天线处理和广播,并且在一个传输跨度内广播覆盖范围内的用户终端 区。

    Eigenvalue decomposition and singular value decomposition of matrices using jacobi rotation
    8.
    发明申请
    Eigenvalue decomposition and singular value decomposition of matrices using jacobi rotation 有权
    使用雅可比旋转的矩阵的特征值分解和奇异值分解

    公开(公告)号:US20060155798A1

    公开(公告)日:2006-07-13

    申请号:US11280596

    申请日:2005-11-15

    IPC分类号: G06F7/52

    摘要: Techniques for decomposing matrices using Jacobi rotation are described. Multiple iterations of Jacobi rotation are performed on a first matrix of complex values with multiple Jacobi rotation matrices of complex values to zero out the off-diagonal elements in the first matrix. For each iteration, a submatrix may be formed based on the first matrix and decomposed to obtain eigenvectors for the submatrix, and a Jacobi rotation matrix may be formed with the eigenvectors and used to update the first matrix. A second matrix of complex values, which contains orthogonal vectors, is derived based on the Jacobi rotation matrices. For eigenvalue decomposition, a third matrix of eigenvalues may be derived based on the Jacobi rotation matrices. For singular value decomposition, a fourth matrix with left singular vectors and a matrix of singular values may be derived based on the Jacobi rotation matrices.

    摘要翻译: 描述了使用雅可比旋转分解矩阵的技术。 对具有复数值的多个Jacobi旋转矩阵的复数值的第一矩阵执行Jacobi旋转的多次迭代,以将第一矩阵中的非对角线元素归零。 对于每个迭代,可以基于第一矩阵形成子矩阵并且被分解以获得子矩阵的特征向量,并且可以与特征向量形成雅可比旋转矩阵并用于更新第一矩阵。 基于Jacobi旋转矩阵导出包含正交向量的第二个复数值矩阵。 对于特征值分解,可以基于Jacobi旋转矩阵导出特征值的第三矩阵。 对于奇异值分解,可以基于雅可比旋转矩阵导出具有左奇异矢量的第四矩阵和奇异值矩阵。

    Efficient computation for eigenvalue decomposition and singular value decomposition of matrices
    9.
    发明申请
    Efficient computation for eigenvalue decomposition and singular value decomposition of matrices 有权
    矩阵特征值分解和奇异值分解的有效计算

    公开(公告)号:US20060106902A1

    公开(公告)日:2006-05-18

    申请号:US11096839

    申请日:2005-03-31

    IPC分类号: G06F15/00

    摘要: For eigenvalue decomposition, a first set of at least one variable is derived based on a first matrix being decomposed and using Coordinate Rotational Digital Computer (CORDIC) computation. A second set of at least one variable is derived based on the first matrix and using a look-up table. A second matrix of eigenvectors of the first matrix is then derived based on the first and second variable sets. To derive the first variable set, CORDIC computation is performed on an element of the first matrix to determine the magnitude and phase of this element, and CORDIC computation is performed on the phase to determine the sine and cosine of this element. To derive the second variable set, intermediate quantities are derived based on the first matrix and used to access the look-up table.

    摘要翻译: 对于特征值分解,基于正在分解的第一矩阵并使用坐标旋转数字计算机(CORDIC)计算来导出至少一个变量的第一组。 基于第一矩阵并使用查找表导出第二组至少一个变量。 然后基于第一和第二变量集导出第一矩阵的特征向量的第二矩阵。 为了导出第一变量集,对第一矩阵的元素执行CORDIC计算,以确定该元素的幅度和相位,并且在相位上执行CORDIC计算以确定该元素的正弦和余弦。 为了导出第二变量集,基于第一矩阵导出中间量并用于访问查找表。