公开(公告)号：US09660709B1

公开(公告)日：2017-05-23

申请号：US14960170

申请日：2015-12-04

Applicant: Uurmi Systems Pvt Ltd

Inventor： Nanda Kishore Chavali ,  Anvesh Reddy Yalla

IPC: H04L27/00 ,  H04L27/06 ,  H04B7/0456 ,  H04L5/00 ,  H04L1/00 ,  H04B1/7105

CPC classification number: H04B7/0456 ,  H04B1/71057 ,  H04B7/0413 ,  H04L1/0054 ,  H04L5/0007

Abstract: A method and a communication receiver have been described for calculating log-likelihood ratios in a communication receiver. The log-likelihood ratio is calculated for each bit of one or more subsymbols of each of the one or more spatial streams by computing effective noise on one or more spatial streams after considering noise terms resulting from MIMO detection estimates of the subsymbols on each spatial stream. Finally, signal to noise ratio is determined for one or more spatial streams from the effective noise and scaling bit log-likelihood ratios with the signal to noise ratio.

公开(公告)号：US08576960B2

公开(公告)日：2013-11-05

申请号：US12628341

申请日：2009-12-01

Applicant: Douglas A. Cairns ,  Gregory E. Bottomley ,  Elias Jonsson

Inventor： Douglas A. Cairns ,  Gregory E. Bottomley ,  Elias Jonsson

IPC: H04L27/06 ,  H04L23/02

CPC classification number: H04L25/03006 ,  H04B1/71057 ,  H04B2201/709727 ,  H04L25/03178 ,  H04L25/03203 ,  H04L25/03331 ,  H04L2025/03426

Abstract: The computation of code-specific channel matrices for an Assisted Maximum Likelihood Detection (AMLD) receiver comprises separately computing high rate matrices that change each symbol period, and a low rate matrix that is substantially constant over a plurality of symbol periods. The high and low rate matrices are combined to generate a code-specific channel matrix for each receiver stage. The high rate matrices include scrambling and spreading code information, and the low rate matrices include information on the net channel response and combining weights. The low rate matrices are efficiently computed by a linear convolution in the frequency domain of the net channel response and combining weights (with zero padding to avoid circular convolution), then transforming the convolution to the time domain and extracting matrix elements. Where the combining weights are constant across stages, a common code-specific channel matrix may be computed and used in multiple AMLD receiver stages.

Abstract translation: 用于辅助最大似然检测（AMLD）接收机的代码特定信道矩阵的计算包括分别计算改变每个符号周期的高速率矩阵和在多个符号周期上基本上恒定的低速率矩阵。 组合高速和低速率矩阵以为每个接收机级生成代码特定的信道矩阵。 高速率矩阵包括加扰和扩展码信息，低速率矩阵包括关于网络信道响应和组合权重的信息。 低速率矩阵通过网络通道响应的频域中的线性卷积和组合权重（零填充以避免循环卷积）有效地计算，然后将卷积变换到时域并提取矩阵元素。 在组合权重跨越阶段恒定的情况下，可以在多个AMLD接收机阶段中计算和使用公共的特定码通道矩阵。

公开(公告)号：US08457255B2

公开(公告)日：2013-06-04

申请号：US12553285

申请日：2009-09-03

Applicant: Jorgen S. Nielsen

Inventor： Jorgen S. Nielsen

IPC: H04L27/06

CPC classification number: H04B1/71057 ,  H04L25/03178 ,  H04L27/2332 ,  H04L2027/003 ,  H04L2027/0042 ,  H04L2027/0046 ,  H04L2027/0067 ,  H04L2027/0085

Abstract: A method of improving sensitivity in the demodulation of a received signal by a receiver over an arbitrary measurement time epoch, said method comprising the steps of correlating said received signal with a local replica of pseudo noise code in a coherent fashion creating a correlation signal and utilizing a Viterbi phase state keying trellis demodulation with a variable resolution of phase states over 0 to 360° to demodulate the radio frequency phase trajectory of said correlation signal throughout the measurement time epoch for improving sensitivity in the demodulation of a received signal.

Abstract translation: 一种提高接收机在任意测量时间周期上解调接收信号的灵敏度的方法，所述方法包括以下步骤：将所述接收信号与相干方式的伪噪声码的局部副本相关，产生相关信号并利用 在0到360°的相位状态的可变分辨率的维特比相位状态键控网格解调，以在整个测量时间周期解调所述相关信号的射频相位轨迹，以改善接收信号的解调中的灵敏度。

公开(公告)号：US08107549B2

公开(公告)日：2012-01-31

申请号：US11564261

申请日：2006-11-28

Applicant: Christoph Arnold Joetten ,  George Jongren ,  Ivan Jesus Fernandez-Corbaton

Inventor： Christoph Arnold Joetten ,  George Jongren ,  Ivan Jesus Fernandez-Corbaton

IPC: H04B7/02

CPC classification number: H04L25/03019 ,  H04B1/71057 ,  H04B1/7117 ,  H04B1/712 ,  H04B2201/70701 ,  H04L5/023 ,  H04L25/0226 ,  H04L27/2647 ,  H04L2025/03426

Abstract: Techniques for receiving a MIMO transmission are described. A receiver processes received data from multiple receive antennas in multiple stages. A first stage performs front-end filtering/equalization on the received data with a front-end filter to process non on-time signal components in the multiple received signals. A second stage processes the filtered data with one or more combiner matrices to combine on-time signal components for multiple transmitted signals. For a MIMO-CDM transmission, a single front-end filter may be used for all channelization codes, and a different combiner matrix may be used for each channelization code. Partitioning the receiver processing into multiple stages simplifies derivation of the front-end filter and combiner matrices while achieving good performance. The front-end filter and combiner matrices may be updated separately at the same or different rates.

Abstract translation: 描述了用于接收MIMO传输的技术。 接收机以多个阶段处理来自多个接收天线的接收数据。 第一级利用前端滤波器对接收到的数据执行前端滤波/均衡，以处理多个接收信号中的非接通时间信号分量。 第二级利用一个或多个组合器矩阵处理滤波后的数据以组合多个发射信号的准时信号分量。 对于MIMO-CDM传输，单个前端滤波器可以用于所有信道化码，并且可以对每个信道化码使用不同的组合器矩阵。 将接收机处理分为多个阶段，简化了前端滤波器和组合器矩阵的推导，同时实现了良好的性能。 前端滤波器和组合器矩阵可以以相同或不同的速率单独更新。

公开(公告)号：US20070127557A1

公开(公告)日：2007-06-07

申请号：US11502178

申请日：2006-08-09

Applicant: Parvathanathan Subrahmanya ,  Inyup Kang ,  Jia Fei ,  Rajesh Sundaresan

Inventor： Parvathanathan Subrahmanya ,  Inyup Kang ,  Jia Fei ,  Rajesh Sundaresan

IPC: H04B1/00 ,  H03H7/30

CPC classification number: H04B1/71057 ,  H04B7/0669 ,  H04B7/0673 ,  H04B7/0845 ,  H04L25/03044 ,  H04L25/03292 ,  H04L2025/03509

Abstract: This disclosure describes equalization techniques for spread spectrum wireless communication. The techniques may involve estimating a channel impulse response, estimating channel variance, and selecting filter coefficients for an equalizer based on the estimated channel impulse response and the estimated channel variance. Moreover, in accordance with this disclosure, the channel variance estimation involves estimation of two or more co-variances for different received samples. Importantly, the equalizer is “fractionally spaced,” which means that the equalizer defines fractional filtering coefficients (filter taps), unlike conventional equalizers that presume that filter coefficients are defined at integer chip spacing. The techniques can allow the equalizer to account for antenna diversity, such as receive diversity, transmit diversity, or possibly both.

Abstract translation: 本公开描述了用于扩频无线通信的均衡技术。 这些技术可以包括基于所估计的信道脉冲响应和所估计的信道方差估计信道脉冲响应，估计信道方差，以及为均衡器选择滤波器系数。 此外，根据本公开，信道方差估计涉及对于不同接收样本的两个或多个协方差的估计。 重要的是，均衡器是“分数间隔”的，这意味着均衡器定义了分数滤波系数（滤波器抽头），不同于传统的均衡器，假设滤波器系数是以整数芯片间隔定义的。 这些技术可以允许均衡器考虑天线分集，例如接收分集，发射分集，或者可能两者。

公开(公告)号：US20060034350A1

公开(公告)日：2006-02-16

申请号：US10534735

申请日：2002-11-27

Applicant: Jorgen Nielsen

Inventor： Jorgen Nielsen

IPC: H04B1/707 ,  H03D1/00

CPC classification number: H04B1/71057 ,  H04L25/03178 ,  H04L27/2332 ,  H04L2027/003 ,  H04L2027/0042 ,  H04L2027/0046 ,  H04L2027/0067 ,  H04L2027/0085

Abstract: A method and system of improving sensitivity in the demodulation of a received signal over an arbitrary measurement time epoch, the method comprising the steps of: correlating the received signal in a coherent fashion (80); and utilizing a Viterbi phase state keying trellis demodulation with a variable resolution of phase states over 360° to demodulate the radio frequency phase trajectory of the signal throughout the measurement time epoch (70); and the system comprising a receiver for receiving a direct sequence spread spectrum signal, the receiver comprising: an antenna (10) for receiving the direct sequence spread spectrum signal; a downconverter (40) for downconverting the received signal, producing a downconverted signal; an analog to digital converter (60) to convert the downconverted signal to a digital signal; a despreader (80) for despreading and coherently correlating the digital signal to a known signal, creating a despread signal; and a processor (70) for applying a Viterbi algorithm to the despread signal.

Abstract translation: 一种改善在任意测量时间周期上解调接收信号的灵敏度的方法和系统，该方法包括以下步骤：以一致的方式对所接收的信号进行相关（80）; 并利用具有超过360°的相位状态的可变分辨率的维特比相位状态键控网格解调来解调整个测量时间周期（70）中的信号的射频相位轨迹; 并且所述系统包括用于接收直接序列扩频信号的接收机，所述接收机包括：用于接收直接序列扩频信号的天线（10）; 下变频器（40），用于下变频接收的信号，产生下变频信号; 模数转换器（60），用于将下变频信号转换成数字信号; 解扩器（80），用于将数字信号与已知信号进行解扩和相干相关，产生解扩信号; 以及用于将Viterbi算法应用于去扩展信号的处理器（70）。

公开(公告)号：US06901103B2

公开(公告)日：2005-05-31

申请号：US10050399

申请日：2002-01-15

Applicant: Srikant Jayaraman ,  Ivan Jesus Fernandez Corbaton ,  John Edward Smee

Inventor： Srikant Jayaraman ,  Ivan Jesus Fernandez Corbaton ,  John Edward Smee

IPC: H03M13/01 ,  H04B1/7105 ,  H04B1/712 ,  H04L1/00 ,  H04L1/02 ,  H04B1/69

CPC classification number: H04L1/005 ,  H04B1/71057 ,  H04B1/712 ,  H04L1/0054 ,  H04L1/02

Abstract: Methods and apparatus are presented herein for determining log likelihood ratios (LLRs) for code symbols. Pilot and code symbols are transmitted over diversity channels, which can be modeled as a slowly time varying system. A formulation for a multipath gain vector is derived herein based on the slowly time varying model. The multipath gain vector is then solved using iterative procedures. Using the solved multipath gain vector, the LLRs for code symbols are computed.

Abstract translation: 本文给出了用于确定代码符号的对数似然比（LLR）的方法和装置。 导频和码符号在分集信道上传输，可以将其建模为缓慢时变的系统。 本文基于缓慢时间变化的模型导出多径增益矢量的公式。 然后使用迭代程序求解多径增益矢量。 使用求解的多径增益矢量，计算代码符号的LLR。

公开(公告)号：US06826140B2

公开(公告)日：2004-11-30

申请号：US10251187

申请日：2002-09-20

Applicant: Karl D. Brommer ,  Robert B. MacLeod ,  Michael P. Schmidt

Inventor： Karl D. Brommer ,  Robert B. MacLeod ,  Michael P. Schmidt

IPC: G11B700

CPC classification number: G11B7/14 ,  G11B5/012 ,  G11B5/488 ,  G11B5/4886 ,  G11B5/4969 ,  G11B5/4976 ,  G11B5/4992 ,  G11B11/10515 ,  G11B20/10 ,  G11B20/10009 ,  G11B20/1217 ,  G11B20/22 ,  G11B2020/1238 ,  G11B2020/1288 ,  G11B2020/1292 ,  H04B1/71057 ,  H04B7/0851 ,  H04L1/06 ,  H04L1/20 ,  H04L1/24 ,  H04L25/03159 ,  H04L25/03171 ,  H04L25/03203 ,  H04L25/03331

Abstract: A processing scheme for digital storage media using multi-user detection to separate tracks of data or remove interference from neighboring tracks. In one embodiment, data is written on a plurality of tracks positioned sufficiently close together so that multiple tracks are detected simultaneously by the read access sensor. Upon scanning the surface for data, the read element simultaneously receives the data signals from a plurality of tracks. Joint detection signal processing resolves the interference and data bits from the multiple sensed tracks, enabling closer packing of data with minimal guard space.

Abstract translation: 一种用于使用多用户检测的数字存储介质的处理方案，用于分离数据轨迹或消除来自相邻轨道的干扰。 在一个实施例中，将数据写在多个轨道上，这些磁道足够靠近在一起，以便读取访问传感器同时检测多个磁道。 在扫描表面以获得数据时，读取元件同时从多个轨道接收数据信号。 联合检测信号处理解决来自多个感测轨迹的干扰和数据位，使得能够以最小的保护空间更紧密地打包数据。

公开(公告)号：US06765951B2

公开(公告)日：2004-07-20

申请号：US10047614

申请日：2002-01-15

Applicant: Markus Doetsch ,  Peter Jung ,  Jörg Plechinger ,  Peter Schmidt ,  Michael Schneider ,  Tideya Kella

Inventor： Markus Doetsch ,  Peter Jung ,  Jörg Plechinger ,  Peter Schmidt ,  Michael Schneider ,  Tideya Kella

IPC: H04B1530

CPC classification number: H04B1/71057 ,  H04B1/712 ,  H04L25/0204 ,  H04L25/0226

Abstract: A method for estimating a channel impulse response of a mobile radio channel is described. The mobile radio channel is accessed over a wide bandwidth by a code division multiplex method. A second mobile radio channel continuously transmits sequences to a multiplicity of mobile radio receivers, and the sequences are known to each of the multiplicity of mobile radio receivers. The delay parameters of the mobile radio channel are estimated using the sequences transmitted via the second mobile radio channel. The mobile radio receiver is adjusted in accordance with the delay parameters estimated and weighting factors of the mobile radio channel are determined.

Abstract translation: 描述了用于估计移动无线电信道的信道脉冲响应的方法。 移动无线电信道通过码分多址方式在宽带宽上被访问。 第二移动无线电信道连续向多个移动无线电接收机发送序列，并且多个移动无线电接收机中的每一个都知道这些序列。 使用经由第二移动无线电信道发送的序列来估计移动无线电信道的延迟参数。 移动无线电接收机根据估计的延迟参数进行调整，确定移动无线电信道的加权因子。

公开(公告)号：US20030198303A1

公开(公告)日：2003-10-23

申请号：US10228787

申请日：2002-08-26

Inventor： Matthew A. Taylor ,  Joshua D. Niedzwiecki ,  Robert B. MacLeod

IPC: H04L027/06 ,  H04B001/10

CPC classification number: H04B1/71057 ,  H04B7/0851 ,  H04L1/06 ,  H04L1/20 ,  H04L1/24

Abstract: A Parameter Estimator for accurately estimating signature responses of multiple co-channel interfering digital transmission signals. The Parameter Estimator is used in a Multiuser Detection (MUD) Receiver to significantly reduce the error rate. The Parameter Estimator comprises a plurality of software components, including a Signature Waveform Estimator, Training Sequence Locator, Noise Estimator, Active Users Tester, Initial Transformation Matrix Builder, a Transformation Matrix Rebuilder, and a Transformation Matrix Selector, and generates an estimated noise power, a training sequence index and estimated signature waveforms.

Abstract translation: 一种用于准确估计多个同信道干扰数字传输信号的签名响应的参数估计器。 参数估计器用于多用户检测（MUD）接收器，以显着降低错误率。 参数估计器包括多个软件组件，包括签名波形估计器，训练序列定位器，噪声估计器，主动用户测试器，初始变换矩阵生成器，变换矩阵重构器和变换矩阵选择器，并且产生估计的噪声功率， 训练序列索引和估计的签名波形。