Transmitter characterization for digital pre-distortion using offset preamble subcarriers
    1.
    发明授权
    Transmitter characterization for digital pre-distortion using offset preamble subcarriers 有权
    使用偏移前导码副载波进行数字预失真的发射机特性

    公开(公告)号:US08218677B2

    公开(公告)日:2012-07-10

    申请号:US12396171

    申请日:2009-03-02

    IPC分类号: H04L25/49

    CPC分类号: H04L27/368 H04L27/2626

    摘要: Techniques are provided to pre-distort a signal that is transmitted by a transmitter of a wireless communication device, e.g., a device configured for wireless radio frequency communication. The transmitter of the device inherently introduces distortion to the baseband signal to be transmitted. In at least one frame of a baseband signal to be transmitted, at least one subcarrier in a preamble of the frame is shifted in frequency such that the at least one subcarrier is offset from a normal subcarrier frequency position. The at least one frame of the baseband signal is supplied to the transmitter that is configured to produce a transmit signal for transmission. The transmit signal at an output of the transmitter is sampled or detected and inter-modulation distortion in the transmit signal is determined at one or more frequencies as a result of shifting of the frequency of the at least one subcarrier in the preamble of the at least one frame. The baseband signal is pre-distorted based on the inter-modulation distortion prior to coupling to the transmitter for transmission.

    摘要翻译: 提供技术来预先失真由无线通信设备的发射机发射的信号,例如被配置用于无线射频通信的设备。 设备的发射机固有地将失真引入要发射的基带信号。 在要发送的基带信号的至少一帧中,帧的前导码中的至少一个副载波的频率偏移,使得至少一个副载波偏离正常子载波频率位置。 基带信号的至少一帧被提供给被配置为产生用于传输的发射信号的发射机。 在发送器的输出处的发送信号被采样或检测,并且在一个或多个频率上确定发送信号中的互调失真,作为至少一个子帧的至少一个子载波的频率的移位的结果 一帧。 基带信号在耦合到发射机之前基于互调失真被预失真以进行传输。

    Transmitter Characterization for Digital Pre-Distortion Using Offset Preamble Subcarriers
    2.
    发明申请
    Transmitter Characterization for Digital Pre-Distortion Using Offset Preamble Subcarriers 有权
    使用偏移前导子载波进行数字预失真的发射机特性

    公开(公告)号:US20100220810A1

    公开(公告)日:2010-09-02

    申请号:US12396171

    申请日:2009-03-02

    IPC分类号: H04L25/49

    CPC分类号: H04L27/368 H04L27/2626

    摘要: Techniques are provided to pre-distort a signal that is transmitted by a transmitter of a wireless communication device, e.g., a device configured for wireless radio frequency communication. The transmitter of the device inherently introduces distortion to the baseband signal to be transmitted. In at least one frame of a baseband signal to be transmitted, at least one subcarrier in a preamble of the frame is shifted in frequency such that the at least one subcarrier is offset from a normal subcarrier frequency position. The at least one frame of the baseband signal is supplied to the transmitter that is configured to produce a transmit signal for transmission. The transmit signal at an output of the transmitter is sampled or detected and inter-modulation distortion in the transmit signal is determined at one or more frequencies as a result of shifting of the frequency of the at least one subcarrier in the preamble of the at least one frame. The baseband signal is pre-distorted based on the inter-modulation distortion prior to coupling to the transmitter for transmission.

    摘要翻译: 提供技术来预先失真由无线通信设备的发射机发射的信号,例如被配置用于无线射频通信的设备。 设备的发射机固有地将失真引入要发射的基带信号。 在要发送的基带信号的至少一帧中,帧的前导码中的至少一个副载波的频率偏移,使得至少一个副载波偏离正常子载波频率位置。 基带信号的至少一帧被提供给被配置为产生用于传输的发射信号的发射机。 在发送器的输出处的发送信号被采样或检测,并且在一个或多个频率上确定发送信号中的互调失真,作为至少一个子帧的至少一个子载波的频率的移位的结果 一帧。 基带信号在耦合到发射机之前基于互调失真被预失真以进行传输。

    Method and system for improving timing position estimation in wireless communications networks
    3.
    发明申请
    Method and system for improving timing position estimation in wireless communications networks 有权
    用于改善无线通信网络中的定时位置估计的方法和系统

    公开(公告)号:US20080037508A1

    公开(公告)日:2008-02-14

    申请号:US11708734

    申请日:2007-02-21

    IPC分类号: H04B7/212

    CPC分类号: H04W56/008

    摘要: A method for determining timing positions in a wireless communications system comprises creating a time-domain timing detection window from a preamble of a receiving signal, generating a first vector of correlations between sampling points in the time-domain timing detection window and sampling points of a known preamble, identifying a pivot position from the largest correlation value of the first vector and generating second vectors based on the pivot position, generating a third vector comprising the largest elements of the second vectors; generating a fourth vector comprising sums of elements in the second vectors, generating fifth and sixth vectors comprising a sum of subsets of the third and fourth vectors, respectively, calculating a seventh vector using the fifth and sixth vectors according to a predetermined equation, and selecting an index of one element from the fifth and seventh vectors to be the timing position according to a predetermined rule.

    摘要翻译: 一种用于确定无线通信系统中的定时位置的方法包括:从接收信号的前导码创建时域定时检测窗口,产生时域定时检测窗口中的采样点之间的第一相关矢量,以及 根据所述第一矢量的最大相关值识别枢轴位置,并且基于所述枢轴位置生成第二矢量,生成包括所述第二矢量的最大元素的第三矢量; 生成包括第二向量中的元素之和的第四矢量,分别产生包括第三和第四矢量的子集合的第五和第六矢量,根据预定方程式使用第五和第六矢量来计算第七矢量,以及选择 根据预定规则,从第五和第七向量的一个元素的索引为定时位置。

    Method and system for improving timing position estimation in wireless communications networks
    4.
    发明授权
    Method and system for improving timing position estimation in wireless communications networks 有权
    用于改善无线通信网络中的定时位置估计的方法和系统

    公开(公告)号:US07876863B2

    公开(公告)日:2011-01-25

    申请号:US11708734

    申请日:2007-02-21

    IPC分类号: H03D1/00

    CPC分类号: H04W56/008

    摘要: A method for determining timing positions in a wireless communications system comprises creating a time-domain timing detection window from a preamble of a receiving signal, generating a first vector of correlations between sampling points in the time-domain timing detection window and sampling points of a known preamble, identifying a pivot position from the largest correlation value of the first vector and generating second vectors based on the pivot position, generating a third vector comprising the largest elements of the second vectors; generating a fourth vector comprising sums of elements in the second vectors, generating fifth and sixth vectors comprising a sum of subsets of the third and fourth vectors, respectively, calculating a seventh vector using the fifth and sixth vectors according to a predetermined equation, and selecting an index of one element from the fifth and seventh vectors to be the timing position according to a predetermined rule.

    摘要翻译: 一种用于确定无线通信系统中的定时位置的方法包括:从接收信号的前导码创建时域定时检测窗口,产生时域定时检测窗口中的采样点之间的第一相关矢量,以及 根据所述第一矢量的最大相关值识别枢轴位置,并且基于所述枢轴位置生成第二矢量,生成包括所述第二矢量的最大元素的第三矢量; 生成包括第二向量中的元素和的第四矢量,分别生成包括第三和第四矢量的子集合的第五和第六矢量,根据预定方程式使用第五和第六矢量来计算第七矢量,以及选择 根据预定规则,从第五和第七向量的一个元素的索引为定时位置。

    Implicit Spatial Matrix Expansion Determination for MIMO Wireless Communication Systems
    5.
    发明申请
    Implicit Spatial Matrix Expansion Determination for MIMO Wireless Communication Systems 有权
    MIMO无线通信系统的隐式空间矩阵扩展确定

    公开(公告)号:US20120328033A1

    公开(公告)日:2012-12-27

    申请号:US13167790

    申请日:2011-06-24

    IPC分类号: H04L27/28

    摘要: Techniques are provided to allow for implicit determination of the full spatial signature of a wireless channel between first and second wireless devices for multiple-input multiple-output (MIMO) wireless communication between the first and second wireless devices. The first wireless device receives uplink signals at a plurality of antennas of the first wireless device that are transmitted via a plurality of antennas of a second wireless device. Values at a plurality of subcarriers of the received signals across the plurality of antennas of the first wireless device are derived. Using a sliding window for groups of adjacent subcarriers, downlink beamforming weights are computed for each group of subcarriers using channel information of one or more proximate groups of subcarriers. The downlink beamforming weights for the respective groups of subcarriers are applied to a number of spatial streams in a downlink transmission to be transmitted to the second wireless device.

    摘要翻译: 提供技术以允许在第一和第二无线设备之间的第一和第二无线设备之间的无线信道的全空间签名的隐含确定用于第一和第二无线设备之间的多输入多输出(MIMO)无线通信。 第一无线设备在经由第二无线设备的多个天线发送的第一无线设备的多个天线处接收上行链路信号。 导出跨越第一无线设备的多个天线的接收信号的多个子载波的值。 使用相邻子载波组的滑动窗口,使用一个或多个邻近子载波组的信道信息为每组子载波组计算下行链路波束形成权重。 将各个子载波组的下行链路波束成形加权应用于要发送到第二无线设备的下行链路传输中的多个空间流。

    Implicit spatial matrix expansion determination for MIMO wireless communication systems
    6.
    发明授权
    Implicit spatial matrix expansion determination for MIMO wireless communication systems 有权
    MIMO无线通信系统的隐式空间矩阵扩展确定

    公开(公告)号:US08761291B2

    公开(公告)日:2014-06-24

    申请号:US13167790

    申请日:2011-06-24

    IPC分类号: H04B7/02 H04L1/02

    摘要: Techniques are provided to allow for implicit determination of the full spatial signature of a wireless channel between first and second wireless devices for multiple-input multiple-output (MIMO) wireless communication between the first and second wireless devices. The first wireless device receives uplink signals at a plurality of antennas of the first wireless device that are transmitted via a plurality of antennas of a second wireless device. Values at a plurality of subcarriers of the received signals across the plurality of antennas of the first wireless device are derived. Using a sliding window for groups of adjacent subcarriers, downlink beamforming weights are computed for each group of subcarriers using channel information of one or more proximate groups of subcarriers. The downlink beamforming weights for the respective groups of subcarriers are applied to a number of spatial streams in a downlink transmission to be transmitted to the second wireless device.

    摘要翻译: 提供技术以允许在第一和第二无线设备之间的第一和第二无线设备之间的无线信道的全空间签名的隐含确定用于第一和第二无线设备之间的多输入多输出(MIMO)无线通信。 第一无线设备在经由第二无线设备的多个天线发送的第一无线设备的多个天线处接收上行链路信号。 导出跨越第一无线设备的多个天线的接收信号的多个子载波的值。 使用相邻子载波组的滑动窗口,使用一个或多个邻近子载波组的信道信息为每组子载波组计算下行链路波束形成权重。 将各个子载波组的下行链路波束成形加权应用于要发送到第二无线设备的下行链路传输中的多个空间流。

    Reducing the peak-to-average power ratio of a signal
    7.
    发明申请
    Reducing the peak-to-average power ratio of a signal 有权
    降低信号的峰均功率比

    公开(公告)号:US20070197210A1

    公开(公告)日:2007-08-23

    申请号:US11361641

    申请日:2006-02-23

    IPC分类号: H04Q7/20

    CPC分类号: H04L27/2624

    摘要: Reducing the peak-to-average power ratio of a signal comprises receiving the input signal, where the input signal is associated with at least one unacceptable frequency range. The input signal is clipped about an amplitude range to yield a clipped signal and clipped information, where the clipped information represents intermodulation products. The clipped information is filtered to yield an error signal. The error signal represents a subset of the intermodulation products, where an intermodulation product of the subset corresponds to the unacceptable frequency range. The error signal is subtracted from the input signal to yield an output signal.

    摘要翻译: 降低信号的峰均功率比包括接收输入信号,其中输入信号与至少一个不可接受的频率范围相关联。 输入信号被约束在幅度范围内以产生剪辑信号和剪辑信息,其中剪辑的信息表示互调产物。 被剪辑的信息被过滤以产生错误信号。 误差信号表示互调产物的子集,其中子集的互调乘积对应于不可接受的频率范围。 从输入信号中减去误差信号,产生输出信号。

    ADAPTIVE CLIPPING OF SYMBOLS BASED ON SIGNAL QUALITY
    8.
    发明申请
    ADAPTIVE CLIPPING OF SYMBOLS BASED ON SIGNAL QUALITY 审中-公开
    基于信号质量的符号自适应剪辑

    公开(公告)号:US20120082262A1

    公开(公告)日:2012-04-05

    申请号:US12896994

    申请日:2010-10-04

    IPC分类号: H04L25/03 H04L27/00

    CPC分类号: H04L27/2623 H04L27/2624

    摘要: Techniques are provided for crest factor reduction of a symbol to be transmitted by a communication device. The symbol may be an orthogonal frequency division multiplexed (OFDM) formatted symbol. In a communication device, samples of the symbol are clipped with a clipping level. A signal quality of the symbol is computed after it is clipped. A determination is made as to whether the signal quality satisfies a predetermined criterion. When the signal quality does not satisfy the predetermined criterion, the clipping level is adjusted. The clipping, computing, determining and adjusting operations are repeated until the signal quality satisfies the predetermined criterion. The symbol clipped by the clipping level determined to result in satisfying the predetermined criterion is output for supply to a transmitter in the communication device. Techniques for computing for error vector magnitude that are faster and less computationally intensive are provided, as well as a computation for distortion that can be used as a measure of error vector magnitude.

    摘要翻译: 提供技术用于通过通信设备发送的符号的波峰因数降低。 符号可以是正交频分复用(OFDM)格式的符号。 在通信设备中,符号的样本被剪切级别。 符号的信号质量在剪切后计算。 确定信号质量是否满足预定标准。 当信号质量不满足预定标准时,调整限幅电平。 重复削波,计算,确定和调整操作,直到信号质量满足预定标准。 输出被限定为导致满足预定标准的限幅电平的符号,以供给通信装置中的发送器。 提供了用于计算更快更少计算密集度的误差矢量幅度的技术,以及可用作误差矢量幅度的度量的失真计算。

    System and method for improving signal to quantization noise ratio of an OFDMA modulator
    9.
    发明申请
    System and method for improving signal to quantization noise ratio of an OFDMA modulator 有权
    用于改善OFDMA调制器的信号到量化噪声比的系统和方法

    公开(公告)号:US20070086534A1

    公开(公告)日:2007-04-19

    申请号:US11582832

    申请日:2006-10-17

    IPC分类号: H04K1/10

    摘要: A fixed-point IFFT device in an OFDMA digital modulator is disclosed, which comprises a sub-carrier activity detector configured to detect a number of active sub-carriers in an OFDMA symbol set being transmitted in a given OFDMA symbol period, a scale termination calculator configured to generate an output for determining at which stage to terminate the IFFT scaling as a predetermined function of the number of active sub-carriers, a scaling controller configured to generate a plurality of control signals based on the output of the scale termination calculator, and an IFFT unit having a plurality of scaling stages each of which is controlled by one of the generated control signals.

    摘要翻译: 公开了一种OFDMA数字调制器中的定点IFFT装置,其包括子载波活动检测器,其被配置为检测在给定OFDMA符号周期中发送的OFDMA符号集中的多个活动子载波,标度终止计算器 被配置为生成用于确定在哪个阶段终止IFFT缩放作为活动子载波数量的预定函数的输出,缩放控制器被配置为基于缩放终止计算器的输出生成多个控制信号,以及 具有多个缩放级的IFFT单元,每个缩放级由所生成的控制信号之一控制。