利索-全球专利检索

  1. 登录
  2. 注册

搜索结果

118 条记录 (耗时 0.027 秒)

    Rate adaptive transmission scheme for MIMO systems
    11.
    发明授权
    Rate adaptive transmission scheme for MIMO systems 有权
    MIMO系统速率自适应传输方案

    公开(公告)号：US06873606B2

    公开(公告)日：2005-03-29

    申请号：US10367234

    申请日：2003-02-14

    申请人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

    发明人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

    IPC分类号： H04B7/00 ,  H04B7/005 ,  H04B7/04 ,  H04B7/06 ,  H04B7/08 ,  H04J99/00 ,  H04L1/00 ,  H04L1/06 ,  H04B1/02

    CPC分类号： H04L1/0618 ,  H04B7/0417 ,  H04B7/0443 ,  H04B7/0465 ,  H04B7/0615 ,  H04B7/0891 ,  H04W52/34 ,  H04W52/42

    摘要： A rate adaptive transmission scheme for MIMO systems, which can transmit a variable number of data symbol streams, provide transmit diversity for each data symbol stream, and fully utilize the total transmit power of the system and the full power of each antenna. In one method, at least one data symbol stream is received for transmission from a plurality of antennas. Each data symbol stream is scaled with a respective weight corresponding to the amount of transmit power allocated to that stream. The scaled data symbol stream(s) are multiplied with a transmit basis matrix to provide a plurality of transmit symbol streams for the plurality of antennas. The transmit basis matrix (e.g., a Walsh-Hadamard matrix or a DFT matrix) is defined such that each data symbol stream is transmitted from all antennas and each transmit symbol stream is transmitted at (or near) the full power for the associated antenna.

    摘要翻译： 可以传输可变数量的数据符号流的MIMO系统的速率自适应传输方案为每个数据符号流提供发射分集，并且充分利用系统的总发射功率和每个天线的全功率。 在一种方法中，接收至少一个数据符号流用于从多个天线发射。 每个数据符号流用对应于分配给该流的发射功率的量的相应权重进行缩放。 缩放的数据符号流与发射基矩阵相乘以为多个天线提供多个发射符号流。 定义发射基矩阵（例如，沃尔什 - 哈达玛矩阵或DFT矩阵），使得每个数据符号流从所有天线发送，并且每个发射符号流以（或接近）相关天线的全功率发射。

    Rate adaptive transmission scheme for mimo systems
    12.
    发明申请
    Rate adaptive transmission scheme for mimo systems 有权
    mimo系统的速率自适应传输方案

    公开(公告)号：US20050013239A1

    公开(公告)日：2005-01-20

    申请号：US10919698

    申请日：2004-08-16

    申请人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

    发明人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

    IPC分类号： H04B7/00 ,  H04B7/005 ,  H04B7/04 ,  H04B7/06 ,  H04B7/08 ,  H04J99/00 ,  H04L1/00 ,  H04L1/06 ,  H04J11/00 ,  H04Q7/00

    CPC分类号： H04L1/0618 ,  H04B7/0417 ,  H04B7/0443 ,  H04B7/0465 ,  H04B7/0615 ,  H04B7/0891 ,  H04W52/34 ,  H04W52/42

    摘要： A rate adaptive transmission scheme for MIMO systems, which can transmit a variable number of data symbol streams, provide transmit diversity for each data symbol stream, and fully utilize the total transmit power of the system and the full power of each antenna. In one method, at least one data symbol stream is received for transmission from a plurality of antennas. Each data symbol stream is scaled with a respective weight corresponding to the amount of transmit power allocated to that stream. The scaled data symbol stream(s) are multiplied with a transmit basis matrix to provide a plurality of transmit symbol streams for the plurality of antennas. The transmit basis matrix (e.g., a Walsh-Hadamard matrix or a DFT matrix) is defined such that each data symbol stream is transmitted from all antennas and each transmit symbol stream is transmitted at (or near) the full power for the associated antenna.

    摘要翻译： 可以传输可变数量的数据符号流的MIMO系统的速率自适应传输方案为每个数据符号流提供发射分集，并且充分利用系统的总发射功率和每个天线的全功率。 在一种方法中，接收至少一个数据符号流用于从多个天线发射。 每个数据符号流用对应于分配给该流的发射功率的量的相应权重进行缩放。 缩放的数据符号流与发射基矩阵相乘以为多个天线提供多个发射符号流。 定义发射基矩阵（例如，沃尔什 - 哈达玛矩阵或DFT矩阵），使得每个数据符号流从所有天线发送，并且每个发射符号流以（或接近）相关天线的全功率发射。

    Frequency tracking for communication signals using M-ary orthogonal walsh modulation
    13.
    发明授权
    Frequency tracking for communication signals using M-ary orthogonal walsh modulation 失效
    使用M-正交沃尔什调制的通信信号的频率跟踪

    公开(公告)号：US06330291B1

    公开(公告)日：2001-12-11

    申请号：US08625481

    申请日：1996-03-29

    申请人： Avneesh Agrawal ,  Rajiv Vijayan

    发明人： Avneesh Agrawal ,  Rajiv Vijayan

    IPC分类号： H04L27233

    CPC分类号： H04B1/7085 ,  H04B1/709

    摘要： A frequency tracking loop for a communication system using orthogonal Walsh modulation is provided. The frequency tracking loop includes a correlator (120), such as a fast Hadamard transformation device, and a discriminator (130). The correlator (120) produces a correlation vector (122) representing the result of correlating the input signal with each of a set of Walsh functions, with corresponding index values. The discriminator (130) produces a frequency error signal (ê) based on the correlator (120) output with the highest energy level and other correlator outputs whose indices are related to the index of highest energy correlator output by powers of two. The frequency error signal (ê) is generated by producing a cross product between the highest energy output and one or more of the other related correlator outputs. In further aspects, a filter (140) can be used to further shape the resulting error signal (ê) and form a frequency offset estimate signal ({circumflex over (f)}).

    摘要翻译： 提供了一种使用正交沃尔什调制的通信系统的频率跟踪环路。 频率跟踪环路包括诸如快速哈达玛变换装置的相关器（120）和鉴别器（130）。 相关器（120）产生表示将输入信号与一组沃尔什函数中的每一个相关联的结果与相应索引值相关的向量（122）。 鉴别器（130）基于以最高能级输出的相关器（120）和其他相关器输出产生频率误差信号（ê），其相关指数与两个功率的最高能量相关器输出的指标相关。 频率误差信号（ê）通过产生最高能量输出和一个或多个其它相关相关器输出之间的交叉积来产生。 在另外的方面，可以使用滤波器（140）来进一步调整所得到的误差信号（ê）并形成频率偏移估计信号（{（f（f）}）。

    Peak-to-average power ratio management for multi-carrier modulation in wireless communication systems
    14.
    发明授权
    Peak-to-average power ratio management for multi-carrier modulation in wireless communication systems 有权
    无线通信系统中多载波调制的峰均功率比管理

    公开(公告)号：US08811973B2

    公开(公告)日：2014-08-19

    申请号：US12170560

    申请日：2008-07-10

    申请人： Rajiv Vijayan ,  Avneesh Agrawal ,  Sanjay Jha

    发明人： Rajiv Vijayan ,  Avneesh Agrawal ,  Sanjay Jha

    IPC分类号： H04W4/00

    CPC分类号： H04W72/0453 ,  H04L5/0007 ,  H04L5/0037 ,  H04L5/0066 ,  H04L27/2614 ,  H04W52/343 ,  H04W52/367

    摘要： Techniques for managing peak-to-average power ratio (PAPR) for multi-carrier modulation in wireless communication systems. Different terminals in a multiple-access system may have different required transmit powers. The number of carriers to allocate to each terminal is made dependent on its required transmit power. Terminals with higher required transmit powers may be allocated fewer carriers (associated with smaller PAPR) to allow the power amplifier to operate at higher power levels. Terminals with lower required transmit powers may be allocated more carriers (associated with higher PAPR) since the power amplifier is operated at lower power levels. The specific carriers to assign to the terminals may also be determined by their transmit power levels to reduce out-of-band emissions. Terminals with higher required transmit powers may be assigned with carriers near the middle of the operating band, and terminals with lower required transmit powers may be assigned with carriers near the band edges.

    摘要翻译： 用于管理无线通信系统中多载波调制的峰均功率比（PAPR）的技术。 多址系统中的不同终端可能具有不同的所需传输功率。 分配给每个终端的载波数量取决于其所需的发射功率。 具有更高所需发射功率的终端可以被分配较少的载波（与较小的PAPR相关联），以允许功率放大器在较高的功率电平下工作。 由于功率放大器在较低的功率电平下工作，所以具有较低所需发射功率的终端可以分配更多的载波（与更高的PAPR相关联）。 分配给终端的特定载波也可以由其发射功率电平来确定，以减少带外发射。 具有更高要求的发射功率的终端可以被分配到靠近工作频带中间的载波，并且具有较低所需发射功率的终端可以被分配给带边缘附近的载波。

    PEAK-TO-AVERAGE POWER RATIO MANAGEMENT FOR MULTI-CARRIER MODULATION IN WIRELESS COMMUNICATION SYSTEMS
    17.
    发明申请
    PEAK-TO-AVERAGE POWER RATIO MANAGEMENT FOR MULTI-CARRIER MODULATION IN WIRELESS COMMUNICATION SYSTEMS 有权
    无线通信系统中多载波调制的平均功率比率管理

    公开(公告)号：US20100067474A1

    公开(公告)日：2010-03-18

    申请号：US12622202

    申请日：2009-11-19

    申请人： Rajiv Vijayan ,  Avneesh Agrawal ,  Sanjay Jha

    发明人： Rajiv Vijayan ,  Avneesh Agrawal ,  Sanjay Jha

    IPC分类号： H04W72/04

    CPC分类号： H04W72/0453 ,  H04L5/0007 ,  H04L5/0037 ,  H04L5/0066 ,  H04L27/2614 ,  H04W52/343 ,  H04W52/367

    摘要： Techniques for managing peak-to-average power ratio (PAPR) for multi-carrier modulation in wireless communication systems. Different terminals in a multiple-access system may have different required transmit powers. The number of carriers to allocate to each terminal is made dependent on its required transmit power. Terminals with higher required transmit powers may be allocated fewer carriers (associated with smaller PAPR) to allow the power amplifier to operate at higher power levels. Terminals with lower required transmit powers may be allocated more carriers (associated with higher PAPR) since the power amplifier is operated at lower power levels. The specific carriers to assign to the terminals may also be determined by their transmit power levels to reduce out-of-band emissions. Terminals with higher required transmit powers may be assigned with carriers near the middle of the operating band, and terminals with lower required transmit powers may be assigned with carriers near the band edges.

    摘要翻译： 用于管理无线通信系统中多载波调制的峰均功率比（PAPR）的技术。 多址系统中的不同终端可能具有不同的所需传输功率。 分配给每个终端的载波数量取决于其所需的发射功率。 具有更高所需发射功率的终端可以被分配较少的载波（与较小的PAPR相关联），以允许功率放大器在较高的功率电平下工作。 由于功率放大器在较低的功率电平下工作，所以具有较低所需发射功率的终端可以分配更多的载波（与更高的PAPR相关联）。 分配给终端的特定载波也可以由其发射功率电平来确定，以减少带外发射。 具有更高要求的发射功率的终端可以被分配到靠近工作频带中间的载波，并且具有较低所需发射功率的终端可以被分配给带边缘附近的载波。

    Rate adaptive transmission scheme for MIMO systems
    18.
    发明授权
    Rate adaptive transmission scheme for MIMO systems 有权
    MIMO系统速率自适应传输方案

    公开(公告)号：US07675886B2

    公开(公告)日：2010-03-09

    申请号：US10919698

    申请日：2004-08-16

    申请人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

    发明人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

    IPC分类号： H04B7/00

    CPC分类号： H04L1/0618 ,  H04B7/0417 ,  H04B7/0443 ,  H04B7/0465 ,  H04B7/0615 ,  H04B7/0891 ,  H04W52/34 ,  H04W52/42

    摘要： A rate adaptive transmission scheme for MIMO systems, which can transmit a variable number of data symbol streams, provide transmit diversity for each data symbol stream, and fully utilize the total transmit power of the system and the full power of each antenna. In one method, at least one data symbol stream is received for transmission from a plurality of antennas. Each data symbol stream is scaled with a respective weight corresponding to the amount of transmit power allocated to that stream. The scaled data symbol stream(s) are multiplied with a transmit basis matrix to provide a plurality of transmit symbol streams for the plurality of antennas. The transmit basis matrix (e.g., a Walsh-Hadamard matrix or a DFT matrix) is defined such that each data symbol stream is transmitted from all antennas and each transmit symbol stream is transmitted at (or near) the full power for the associated antenna.

    摘要翻译： 可以传输可变数量的数据符号流的MIMO系统的速率自适应传输方案为每个数据符号流提供发射分集，并且充分利用系统的总发射功率和每个天线的全功率。 在一种方法中，接收至少一个数据符号流用于从多个天线发射。 每个数据符号流用对应于分配给该流的发射功率的量的相应权重进行缩放。 缩放的数据符号流与发射基矩阵相乘以为多个天线提供多个发射符号流。 定义发射基矩阵（例如，沃尔什 - 哈达玛矩阵或DFT矩阵），使得每个数据符号流从所有天线发送，并且每个发射符号流以相关天线的（或接近）全功率发射。

    Efficient employment of digital upsampling using IFFT in OFDM systems for simpler analog filtering
    19.
    发明授权
    Efficient employment of digital upsampling using IFFT in OFDM systems for simpler analog filtering 有权
    在OFDM系统中有效利用使用IFFT的数字上采样进行更简单的模拟滤波

    公开(公告)号：US09042461B2

    公开(公告)日：2015-05-26

    申请号：US11373001

    申请日：2006-03-09

    申请人： Raghuraman Krishnamoorthi ,  Fuyun Ling ,  Rajiv Vijayan

    发明人： Raghuraman Krishnamoorthi ,  Fuyun Ling ,  Rajiv Vijayan

    IPC分类号： H04N7/18 ,  H04L27/26

    CPC分类号： H04L27/2644

    摘要： Systems and methods are provided for transmitting OFDM information via IFFT up-sampling components that transmit data at a higher sampling rate than conventional systems to simplify filter requirements and mitigate leakage between symbols. In one embodiment, an NL point IFFT is performed on a zero inserted set of frequency domain symbols. In another embodiment, the NL point IFFT is further optimized by exploiting the fact that (N−1) L of the frequency domain symbols are zero. This enables an embodiment that consists of a pre-processor that multiplies the input samples by complex phase factors, followed by L point IFFTs.

    摘要翻译： 提供了系统和方法，用于通过IFFT上采样组件传输OFDM信息，该组件以比常规系统更高的采样速率传输数据，以简化滤波器要求并减轻符号之间的泄漏。 在一个实施例中，对零插入的频域符号组执行NL点IFFT。 在另一个实施例中，通过利用频域符号的（N-1）L为零的事实进一步优化NL点IFFT。 这使得能够由预处理器组成的实施例，该预处理器将输入样本乘以复相位因子，随后是L点IFFT。