公开(公告)号：US08265207B1

公开(公告)日：2012-09-11

申请号：US13333106

申请日：2011-12-21

Applicant: Konstantinos Sarrigeorgidis ,  Yanni Chen ,  Leilei Song ,  Kedar Shirali

Inventor： Konstantinos Sarrigeorgidis ,  Yanni Chen ,  Leilei Song ,  Kedar Shirali

IPC: H04L27/06 ,  H03M13/03

CPC classification number: H04L25/067 ,  H03M13/612 ,  H04L1/0045 ,  H04L25/03286 ,  H04L27/2647

Abstract: Methods and apparatus are provided for computing reliability values in a pipeline. A reliability value portion is computed, with control circuitry in a first pipeline stage, based on a difference between a received input signal value and an expected value. The reliability value portion is combined, in a second pipeline stage that follows the first pipeline stage, with a first value derived from the received input signal to generate a first reliability value. A determination is made as to whether to update the first reliability value in a third pipeline stage based on a combination of the first reliability value with a second reliability value that corresponds to a second value derived from the received input signal.

Abstract translation: 提供了用于计算流水线中的可靠性值的方法和装置。 基于接收到的输入信号值和预期值之间的差，计算第一流水线级中的控制电路的可靠性值部分。 在靠近第一流水线级的第二流水线级中，将可靠性值部分与从所接收的输入信号导出的第一值相结合，以产生第一可靠性值。 基于第一可靠性值与对应于从接收的输入信号导出的第二值相对应的第二可靠性值的组合，确定是否更新第三流水线级中的第一可靠性值。

公开(公告)号：US08040982B1

公开(公告)日：2011-10-18

申请号：US11483057

申请日：2006-07-06

Applicant: Rohit Nabar ,  Kedar Shirali

Inventor： Rohit Nabar ,  Kedar Shirali

IPC: H04L27/06 ,  H04L27/28 ,  H04J11/00

CPC classification number: H04L25/0206 ,  H04L25/022 ,  H04L25/0224

Abstract: The disclosed technology relates to estimating the frequency response of a frequency division multiplexed (FDM) channel. In accordance with one aspect of the invention, a channel estimation circuit of a receiver can compute initial estimates of the frequency response of sub-channels in the FDM channel. A phase adjustment circuit can adjust the phase components of the initial estimates to provide phase-adjusted estimates. A smoothing circuit can apply a smoothing operation to the phase-adjusted estimates to provide smoothed phase-adjusted estimates. When necessary, a reverse phase adjustment circuit can reverse the phase adjustment by adjusting the phase components of the smoothed phase-adjusted estimates to provide final channel estimates.

Abstract translation: 所公开的技术涉及估计频分复用（FDM）信道的频率响应。 根据本发明的一个方面，接收机的信道估计电路可以计算FDM信道中子信道的频率响应的初始估计。 相位调整电路可以调整初始估计的相位分量，以提供相位调整的估计。 平滑电路可以对经阶段调整的估计值进行平滑处理，以提供平滑的相位调整估计。 必要时，反向相位调整电路可以通过调整平滑的相位调整估计的相位分量来反转相位调整，以提供最终的信道估计。

公开(公告)号：US20080089396A1

公开(公告)日：2008-04-17

申请号：US11857297

申请日：2007-09-18

Applicant: Hongyuan Zhang ,  Rohit Nabar ,  Kedar Shirali ,  Peter Loc

Inventor： Hongyuan Zhang ,  Rohit Nabar ,  Kedar Shirali ,  Peter Loc

IPC: H04J3/16

CPC classification number: H04B7/0413 ,  H04B7/0617 ,  H04B17/21 ,  H04L25/0204 ,  H04L25/0228 ,  H04L25/03343 ,  H04L2025/03414 ,  H04L2025/03426 ,  H04L2025/03802

Abstract: A transmitter beamforming technique for use in a MIMO wireless communication system determines a partial description of a reverse channel without determining a full dimensional description of the reverse channel. A correction matrix is developed from the partial description of the reverse channel and a description of the forward channel. The correction matrix is used to process signals to be transmitted via the forward channel, and a steering matrix is used to perform beamforming in the forward channel.

Abstract translation: 用于MIMO无线通信系统的发射机波束成形技术确定反向信道的部分描述，而不确定反向信道的全维度描述。 从反向信道的部分描述和正向信道的描述开发校正矩阵。 校正矩阵用于处理要经由正向信道发送的信号，并且使用导引矩阵来在前向信道中执行波束成形。

公开(公告)号：US20080084835A1

公开(公告)日：2008-04-10

申请号：US11866754

申请日：2007-10-03

Applicant: Sandesh Goel ,  Timothy Donovan ,  Ken Ho ,  Yungping Hsu ,  Kedar Shirali ,  Atul Salhotra ,  Tam Tran ,  Chia-Chun Chung

Inventor： Sandesh Goel ,  Timothy Donovan ,  Ken Ho ,  Yungping Hsu ,  Kedar Shirali ,  Atul Salhotra ,  Tam Tran ,  Chia-Chun Chung

IPC: H04B7/00 ,  H04Q7/20

CPC classification number: H04W72/04 ,  H04W74/0808

Abstract: A system includes a signal processing module and a control module. The signal processing module receives a first clear channel assessment (CCA) signal for a first sub-channel of a communication channel, increases a pulse width of the first CCA signal by a predetermined period of time, and generates a second CCA signal. The control module receives the second CCA signal and a third CCA signal for a second sub-channel of the communication channel. The control module transmits data via one of the second sub-channel and the communication channel based on the second and third CCA signals.

Abstract translation: 系统包括信号处理模块和控制模块。 信号处理模块接收通信信道的第一子信道的第一清除信道评估（CCA）信号，将第一CCA信号的脉冲宽度增加预定时间段，并产生第二CCA信号。 控制模块接收第二CCA信号和用于通信信道的第二子信道的第三CCA信号。 控制模块基于第二和第三CCA信号，经由第二子信道和通信信道中的一个发送数据。

公开(公告)号：US06985033B1

公开(公告)日：2006-01-10

申请号：US10753007

申请日：2004-01-06

Applicant: Kedar Shirali ,  King Chun Tsai ,  Wayne Loeb

Inventor： Kedar Shirali ,  King Chun Tsai ,  Wayne Loeb

IPC: H03F1/26

CPC classification number: H03F1/3247 ,  H03F2201/3233

Abstract: An amplifier with adjustable (pre)distortion, a predistortion adjustment circuit, systems and networks including such amplifiers and circuits, and methods for adjusting (pre)distortion in an analog amplifier. The amplifier architecture generally includes (a) a predistortion circuit configured to (i) select a value for a predistortion function from a plurality of different predistortion values, and (ii) apply the selected predistortion value to an input signal to generate a predistorted input signal; (b) an amplifier configured to amplify the predistorted input signal and provide an output signal therefrom; and (c) an adjustment circuit configured to adjust selection of the predistortion function value in response to a predetermined parameter value of the amplifier. By adjusting the predistortion function, the amplifier provides an output signal in a linear power range over a range of amplifier parameter values and avoids overcompensation that can occur when the predistortion signal is not adjustable. Furthermore, the adjustments are made in response to changes in amplifier input and/or control parameters, enabling the amplifier to stay in the linear range, rather than respond to changes that first cause the amplifier to fall out of linearity. The systems generally include the architecture, circuit or an integrated circuit that embodies one or more of the inventive concepts disclosed herein. The methods generally include the steps of (1) predistorting an input signal in accordance with a digital predistortion function to provide a predistorted signal, (2) adjusting the digital predistortion function in response to a predetermined parameter value of an amplifier, and (3) amplifying the predistorted signal with the amplifier to produce the amplified signal.

Abstract translation: 具有可调（预）失真的放大器，预失真调节电路，包括这种放大器和电路的系统和网络，以及用于在模拟放大器中调整（预）失真的方法。 放大器架构通常包括（a）预失真电路，其被配置为（i）从多个不同预失真值中选择预失真函数的值，以及（ii）将所选择的预失真值应用于输入信号以产生预失真输入信号 ; （b）放大器，被配置为放大所述预失真输入信号并从其提供输出信号; 以及（c）调整电路，被配置为响应于所述放大器的预定参数值来调整所述预失真函数值的选择。 通过调整预失真功能，放大器在放大器参数值的范围内提供线性功率范围内的输出信号，并避免在预失真信号不可调时可能发生的过补偿。 此外，响应于放大器输入和/或控制参数的变化进行调整，使得放大器能够保持在线性范围内，而不是响应于首先使放大器脱离线性的变化。 这些系统通常包括体现本文公开的一个或多个发明构思的架构，电路或集成电路。 所述方法通常包括以下步骤：（1）根据数字预失真函数预失真输入信号以提供预失真信号，（2）响应于放大器的预定参数值调整数字预失真函数，以及（3） 用放大器放大预失真信号以产生放大信号。

公开(公告)号：US08391397B2

公开(公告)日：2013-03-05

申请号：US13178387

申请日：2011-07-07

Applicant: Hongyuan Zhang ,  Rohit U. Nabar ,  Kedar Shirali ,  Peter Loc

Inventor： Hongyuan Zhang ,  Rohit U. Nabar ,  Kedar Shirali ,  Peter Loc

IPC: H04B7/02 ,  H04L23/02

CPC classification number: H04B7/0413 ,  H04B7/0617 ,  H04B17/21 ,  H04L25/0204 ,  H04L25/0228 ,  H04L25/03343 ,  H04L2025/03414 ,  H04L2025/03426 ,  H04L2025/03802

Abstract: A transmitter beamforming technique for use in a MIMO wireless communication system determines a partial description of a reverse channel without determining a full dimensional description of the reverse channel. A correction matrix is developed from the partial description of the reverse channel and a description of the forward channel. The correction matrix is used to process signals to be transmitted via the forward channel, and a steering matrix is used to perform beamforming in the forward channel.

Abstract translation: 用于MIMO无线通信系统的发射机波束成形技术确定反向信道的部分描述，而不确定反向信道的全维度描述。 从反向信道的部分描述和正向信道的描述开发校正矩阵。 校正矩阵用于处理要经由正向信道发送的信号，并且使用导引矩阵来在前向信道中执行波束成形。

公开(公告)号：US08224272B1

公开(公告)日：2012-07-17

申请号：US11999482

申请日：2007-12-05

Applicant: Hongyuan Zhang ,  Zhiyu Yang ,  Kedar Shirali ,  Atul Salhotra

Inventor： Hongyuan Zhang ,  Zhiyu Yang ,  Kedar Shirali ,  Atul Salhotra

IPC: H04B17/02 ,  H04B1/16

CPC classification number: H04L27/0012 ,  H04B7/082 ,  H04L23/02 ,  H04L25/0262 ,  H04L27/2071

Abstract: A wireless networking receiver with digital antenna switching selects an antenna with an 802.11b signal based on a signal metric, such as the highest signal quality or highest peak amplitude. In one embodiment, the receiver comprises a plurality of antennas that may each receive one of a plurality of RF signals conforming to the IEEE 802.11b standard. The receiver may have multiple antennas for use with the IEEE 802.11n standard, but may receive signals conforming to the 802.11b standard. The receiver also comprises a carrier sense circuit configured to calculate a signal metric for each of the signals and further configured to generate a selection signal signifying one of the signals, based on the signal metric. The receiver further comprises a multiplexer configured to output one of the signals, based on the selection signal. In another embodiment, a wireless networking receiver comprises signal receiving means, carrier sensing means for calculating and selecting a signal based on a signal metric, and multiplexer means to output the signal. A related method is also disclosed. Other embodiments are provided, and each of the embodiments described herein can be used alone or in combination with one another.

Abstract translation: 具有数字天线切换的无线网络接收机基于诸如最高信号质量或最高峰值幅度的信号度量来选择具有802.11b信号的天线。 在一个实施例中，接收机包括可以各自接收符合IEEE 802.11b标准的多个RF信号中的一个的多个天线。 接收机可以具有用于IEEE 802.11n标准的多个天线，但是可以接收符合802.11b标准的信号。 接收机还包括被配置为计算每个信号的信号度量的载波侦听电路，并进一步被配置为基于信号度量产生表示信号之一的选择信号。 接收机还包括多路复用器，配置为基于选择信号输出信号之一。 在另一个实施例中，无线联网接收机包括信号接收装置，用于基于信号度量计算和选择信号的载波检测装置，以及用于输出信号的多路复用装置。 还公开了相关方法。 提供了其它实施例，并且本文所述的每个实施例可以单独使用或彼此组合使用。

公开(公告)号：US08094744B1

公开(公告)日：2012-01-10

申请号：US12111143

申请日：2008-04-28

Applicant: Leilei Song ,  Rohit U. Nabar ,  Hui-Ling Lou ,  Kedar Shirali

Inventor： Leilei Song ,  Rohit U. Nabar ,  Hui-Ling Lou ,  Kedar Shirali

IPC: H04B7/02

CPC classification number: H04L27/0008 ,  H04L1/0003 ,  H04L1/0009 ,  H04L1/0036 ,  H04L27/22 ,  H04L27/38

Abstract: A system and method of selecting a data detector alternately implement different data detection techniques such as maximum likelihood, zero forcing, and minimum mean square error. Selection of a particular technique may depend upon various factors. In some implementations, a decision whether to employ a specific strategy may be based upon a modulation and coding scheme utilized by the multiple-input, multiple-output (MIMO) system.

Abstract translation: 选择数据检测器的系统和方法交替实现不同的数据检测技术，例如最大似然，迫零和最小均方误差。 特定技术的选择可能取决于各种因素。 在一些实现中，是否采用特定策略的决定可以基于由多输入多输出（MIMO）系统使用的调制和编码方案。

公开(公告)号：US07872962B1

公开(公告)日：2011-01-18

申请号：US11447762

申请日：2006-06-05

Applicant: Rohit Nabar ,  Kedar Shirali ,  Hui-Ling Lou ,  Jungwon Lee

Inventor： Rohit Nabar ,  Kedar Shirali ,  Hui-Ling Lou ,  Jungwon Lee

IPC: H04J11/00

CPC classification number: H04B7/084 ,  H04B7/0615 ,  H04B7/0845 ,  H04B2201/70706 ,  H04L25/0232 ,  H04L27/0014

Abstract: The disclosed technology relates to a communication system and method in which multiple versions of a signal are processed to detect the signal. The communication system can include transmitters that communicate different versions of a signal to a receiver. The different versions are weighted versions of the signal and are communicated on different channels. The weight for a weighted signal is based on an inverse of an estimate of the phase shift of the particular channel to which the weighted signal will be communicated. The weights are also based on a unity gain such that each weighted signal has the same magnitude as the original signal. A receiver that receives the weighted signals processes the received signals to detect the original signal.

Abstract translation: 所公开的技术涉及其中处理多个版本的信号以检测信号的通信系统和方法。 通信系统可以包括将信号的不同版本传送到接收机的发射机。 不同的版本是信号的加权版本，并且在不同的信道上进行通信。 加权信号的权重基于加权信号将被传送到的特定信道的相移的估计的倒数。 权重也基于单位增益，使得每个加权信号具有与原始信号相同的幅度。 接收加权信号的接收机处理接收的信号以检测原始信号。

公开(公告)号：US20100232475A1

公开(公告)日：2010-09-16

申请号：US12788081

申请日：2010-05-26

Applicant: Arul Durai Murugan Palanivelu ,  Hui-Ling Lou ,  Kedar Shirali ,  Rohit U. Nabar ,  Atul Salhotra

Inventor： Arul Durai Murugan Palanivelu ,  Hui-Ling Lou ,  Kedar Shirali ,  Rohit U. Nabar ,  Atul Salhotra

IPC: H04B1/00

CPC classification number: H04B7/0678 ,  H04L1/06

Abstract: A spatial spreading unit is configured to utilize a spatial spreading matrix to distribute two or more encoded spatial data streams to transmission antennas. The spatial spreading matrix has components (i) associated with each row of a row dimension having a number of rows equal to the number of the transmission antennas to be used to transmit the encoded spatial data streams and (ii) associated with each column of a column dimension having a number of columns equal to the number of the encoded spatial data streams to be transmitted. Additionally, the spatial spreading matrix satisfies one or more of the following two constraints: (1) the ratio of squared norms of the sum of the components of a row, for different rows of the spatial spreading matrix, is equal to a first constant sequence, and (2) the ratio of squared norms of the sum of a symbol Sl to be transmitted, when the symbol Sl is equal to 1 or −1, multiplied by each of the components of a row, for different rows of the spatial spreading matrix, is equal to a second constant sequence.

Abstract translation: 空间扩展单元被配置为利用空间扩展矩阵将两个或更多个经编码的空间数据流分配到发射天线。 空间扩展矩阵具有与行尺寸的每行相关联的组件（i），其具有等于要用于发送编码的空间数据流的发送天线的数量的行数，以及（ii）与每个列相关联的 列尺寸具有等于要发送的编码空间数据流的数量的列数。 此外，空间扩展矩阵满足以下两个约束中的一个或多个：（1）对于空间扩展矩阵的不同行，行的分量之和的平方范数的比等于第一常数序列 ，和（2）当符号S1等于1或-1时，要发送的符号S1的和的平方值的比值乘以一行的每个分量，对于不同的空间扩展行 矩阵等于第二个常数序列。