公开(公告)号：US20120142276A1

公开(公告)日：2012-06-07

申请号：US12960283

申请日：2010-12-03

Applicant: Young Geun Cho ,  Aditya Dua ,  Feng Lu ,  Gokhan Mergen ,  Subramanya P.N. Rao ,  Abhinav Gupta ,  Parvathanathan Subrahmanya

Inventor： Young Geun Cho ,  Aditya Dua ,  Feng Lu ,  Gokhan Mergen ,  Subramanya P.N. Rao ,  Abhinav Gupta ,  Parvathanathan Subrahmanya

IPC: H04B17/00

CPC classification number: H04L1/20

Abstract: Methods and apparatuses for data aided channel quality estimation using both pilot and data information are disclosed herein. In one exemplary aspect, a method for estimating channel quality in a wireless communication system is disclosed. The method comprises estimating a pilot noise variance based on a pilot signal received from a base station on a downlink and estimating a data noise variance based on a data signal received from the base station on the downlink. The method also comprises combining the pilot noise variance and the data noise variance to obtain a combined noise variance, and estimating the channel quality based on the combined noise variance.

Abstract translation: 本文公开了使用导频和数据信息的数据辅助信道质量估计的方法和装置。 在一个示例性方面，公开了一种用于估计无线通信系统中的信道质量的方法。 该方法包括基于从下行链路上的基站接收的导频信号来估计导频噪声方差，并且基于在下行链路上从基站接收的数据信号来估计数据噪声方差。 该方法还包括组合导频噪声方差和数据噪声方差以获得组合噪声方差，并且基于组合的噪声方差来估计信道质量。

公开(公告)号：US20120045024A1

公开(公告)日：2012-02-23

申请号：US13033545

申请日：2011-02-23

Applicant: Tao Cui ,  Jia Tang ,  Andrew Sendonaris ,  Atul A. Salvekar ,  Subramanya P.N. Rao ,  Parvathanathan Subrahmanya ,  Lei Xiao ,  Michael L. McCloud ,  Brian Clarke Banister

Inventor： Tao Cui ,  Jia Tang ,  Andrew Sendonaris ,  Atul A. Salvekar ,  Subramanya P.N. Rao ,  Parvathanathan Subrahmanya ,  Lei Xiao ,  Michael L. McCloud ,  Brian Clarke Banister

IPC: H04L27/06

CPC classification number: H04L1/005 ,  H04L1/06 ,  H04L25/03242 ,  H04L25/067

Abstract: Methods and apparatus for receiving, processing, and decoding MIMO transmissions in communications systems are described. A non-Gaussian approximation method for simplifying processing complexity where summations are used is described. Use of a priori information to facilitate determination of log likelihood ratios (LLRs) in receivers using iterative decoders is further described. A Gaussian or non-Gaussian approximation method using a priori information may be used to determine a K-best list of values for summation to generate an LLR is also described.

Abstract translation: 描述了用于在通信系统中接收，处理和解码MIMO传输的方法和装置。 描述了用于简化使用求和的处理复杂度的非高斯近似方法。 进一步描述使用先验信息以便于使用迭代解码器确定接收机中的对数似然比（LLR）。 也可以使用使用先验信息的高斯或非高斯近似方法来确定用于求和以产生LLR的K个最佳值列表。

公开(公告)号：US08074158B2

公开(公告)日：2011-12-06

申请号：US11049991

申请日：2005-02-02

Applicant: Arun Visvanathan ,  Amit Butala ,  Parvathanathan Subrahmanya

Inventor： Arun Visvanathan ,  Amit Butala ,  Parvathanathan Subrahmanya

IPC: G06F11/00

CPC classification number: H04W52/12 ,  H04B1/7172 ,  H04L1/20 ,  H04L1/201 ,  H04L1/208 ,  H04W52/18 ,  H04W52/20 ,  H04W52/24 ,  H04W52/44

Abstract: To perform erasure detection for an intermittently active transport channel with unknown format, a receiver determines an energy metric and a symbol error rate (SER) for a received block with CRC failure. The receiver computes uncorrelated random variables u and v for the received block based on the energy metric and SER, the estimated means and standard deviations of the energy metric and SER, and a correlation coefficient indicative of the correlation between the energy metric and SER. The receiver then evaluates the uncorrelated random variables u and v based on at least one decision criterion and declares the received block to be an erased block or a DTX block based on the result of the evaluation. The decision criterion may be defined based on a target probability of false alarm and adjusted based on another metric, such as a zero state bit, for the received block.

Abstract translation: 为了对具有未知格式的间歇活动传输信道执行擦除检测，接收机确定具有CRC故障的接收块的能量度量和符号错误率（SER）。 接收机基于能量度量和SER，能量度量和SER的估计平均值和标准偏差以及表示能量度量与SER之间的相关性的相关系数，计算接收块的不相关随机变量u和v。 然后，接收机基于至少一个决策标准来评估不相关的随机变量u和v，并且基于评估结果将接收到的块声明为擦除块或DTX块。 可以基于目标误报率概率来定义判定标准，并且基于接收块的另一个度量（例如零状态位）进行调整。

公开(公告)号：US20110208984A1

公开(公告)日：2011-08-25

申请号：US13013381

申请日：2011-01-25

Applicant: Vidyut M. Naware ,  Ketan N. Patel ,  Eugene T. Sy ,  Parvathanathan Subrahmanya

Inventor： Vidyut M. Naware ,  Ketan N. Patel ,  Eugene T. Sy ,  Parvathanathan Subrahmanya

IPC: G06F1/32

CPC classification number: H04W52/0229 ,  H04W52/0238 ,  H04W52/0274 ,  H04W52/029 ,  H04W88/02 ,  Y02D70/1242 ,  Y02D70/1244 ,  Y02D70/126 ,  Y02D70/23

Abstract: User experiences on wireless devices are affected by communication, computation, and user interface capabilities. Another key performance indicator of a wireless device is its battery life. A method, algorithm and apparatus for improving the communication, computation and user interface capabilities of a mobile device is disclosed, which requires the expenditure of less energy and increases battery life. The trade-off between battery life and user experience related to the communication capability is managed by a protocol stack power optimization algorithm that optimally allocates energy resources. The power management algorithm inputs and combines measurements made at various layers of the protocol stack to selectively control a set of actions impacting energy usage. The algorithm maps from a set of measurements to a set of actions that provides the best trade-off between user experience and energy consumption.

Abstract translation: 无线设备的用户体验受通信，计算和用户界面功能的影响。 无线设备的另一个关键性能指标是其电池寿命。 公开了一种用于改善移动设备的通信，计算和用户界面能力的方法，算法和装置，其需要较少的能量消耗并延长电池寿命。 电池寿命与通信能力相关的用户体验之间的权衡由最优分配能源的协议栈功率优化算法进行管理。 功率管理算法输入和组合在协议栈的各个层进行的测量，以选择性地控制影响能量使用的一组动作。 该算法将一组测量映射到提供用户体验和能量消耗之间最佳权衡的一组动作。

公开(公告)号：US07970043B2

公开(公告)日：2011-06-28

申请号：US12860534

申请日：2010-08-20

Applicant: Yan Li ,  Parvathanathan Subrahmanya ,  Naveed Zaman

Inventor： Yan Li ,  Parvathanathan Subrahmanya ,  Naveed Zaman

IPC: H04B1/707

CPC classification number: H04B1/7083 ,  H04B1/70735 ,  H04B1/709

Abstract: A circuit and algorithm are disclosed for a step2 search of a three step search of synchronization channels in a W-CDMA system. A mobile terminal of the CDMA system includes an RF downconverter for receiving I and Q signals. A searcher, responsive to the I and Q signals, includes a first correlator for correlating the I and Q signals with a primary synchronization code on a primary synchronization channel, and a second correlator for correlating I and Q signals with a secondary synchronization code on a secondary synchronization channel. The correlated I and Q signals are added for each of the secondary synchronization codes. An energy calculator and a maximum energy detector use the correlated I and Q signals of both the primary and secondary synchronization channels to detect the most likely scrambling code group of secondary synchronization codes.

Abstract translation: 公开了一种针对W-CDMA系统中的同步信道的三步搜索的步骤2搜索的电路和算法。 CDMA系统的移动终端包括用于接收I和Q信号的RF下变频器。 响应于I和Q信号的搜索器包括用于将I信号与Q信号与主同步信道上的主同步码进行相关的第一相关器，以及用于使I和Q信号与第一同步码相关的第二相关器， 辅同步通道。 为每个辅助同步码添加相关的I和Q信号。 能量计算器和最大能量检测器使用主和次同步信道的相关I和Q信号来检测次同步码的最可能的扰码组。

公开(公告)号：US07933316B2

公开(公告)日：2011-04-26

申请号：US11836941

申请日：2007-08-10

Applicant: Yan Li ,  Parvathanathan Subrahmanya ,  Naveed Zaman

Inventor： Yan Li ,  Parvathanathan Subrahmanya ,  Naveed Zaman

IPC: H04B1/707

CPC classification number: H04B1/7083 ,  H04B1/70735 ,  H04B1/709

Abstract: A circuit and algorithm are disclosed for a step2 search of a three step search of synchronization channels in a W-CDMA system. A mobile terminal of the CDMA system includes an RF downconverter for receiving I and Q signals. A searcher, responsive to the I and Q signals, includes a first correlator for correlating the I and Q signals with a primary synchronization code on a primary synchronization channel, and a second correlator for correlating I and Q signals with a secondary synchronization code on a secondary synchronization channel. The correlated I and Q signals are added for each of the secondary synchronization codes. An energy calculator and a maximum energy detector use the correlated I and Q signals of both the primary and secondary synchronization channels to detect the most likely scrambling code group of secondary synchronization codes.

Abstract translation: 公开了一种针对W-CDMA系统中的同步信道的三步搜索的步骤2搜索的电路和算法。 CDMA系统的移动终端包括用于接收I和Q信号的RF下变频器。 响应于I和Q信号的搜索器包括用于将I信号与Q信号与主同步信道上的主同步码进行相关的第一相关器，以及用于使I和Q信号与第一同步码相关的第二相关器， 辅同步通道。 为每个辅助同步码添加相关的I和Q信号。 能量计算器和最大能量检测器使用主和次同步信道的相关I和Q信号来检测次同步码的最可能的扰码组。

公开(公告)号：US07929652B2

公开(公告)日：2011-04-19

申请号：US11733646

申请日：2007-04-10

Applicant: Farrokh Abrishamkar ,  Mariam Motamed ,  Parvathanathan Subrahmanya

Inventor： Farrokh Abrishamkar ,  Mariam Motamed ,  Parvathanathan Subrahmanya

IPC: H03D1/04 ,  H03K9/00

CPC classification number: H04L25/0228

Abstract: Techniques for performing adaptive channel estimation are described. A receiver derives channel estimates for a wireless channel based on received pilot symbols and at least one estimation parameter. The receiver updates the at least one estimation parameter based on the received pilot symbols. The at least one estimation parameter may be for an innovations representation model of the wireless channel and may be updated based on a cost function with costs defined by prediction errors. In one design, the receiver derives predicted pilot symbols based on the received pilot symbols and the at least one estimation parameter, determines prediction errors based on the received pilot symbols and the predicted pilot symbols, and further derives error gradients based on the prediction errors. The receiver then updates the at least one estimation parameter based on the error gradients and the prediction errors, e.g., if a stability test is satisfied.

Abstract translation: 描述用于执行自适应信道估计的技术。 接收机基于接收的导频符号和至少一个估计参数导出无线信道的信道估计。 接收机基于接收的导频符号来更新至少一个估计参数。 所述至少一个估计参数可以是针对无线信道的创新表示模型，并且可以基于具有由预测误差定义的成本的成本函数来更新。 在一种设计中，接收器基于接收到的导频符号和至少一个估计参数导出预测的导频符号，基于接收到的导频符号和预测的导频符号来确定预测误差，并且还基于预测误差导出误差梯度。 然后，接收器基于误差梯度和预测误差来更新至少一个估计参数，例如，如果满足稳定性测试。

公开(公告)号：US20100135172A1

公开(公告)日：2010-06-03

申请号：US12554202

申请日：2009-09-04

Applicant: Tao Cui ,  Feng Lu ,  Anil Kumar Goteti ,  Vignesh Sethuraman ,  Subramanya P. Rao ,  Parvathanathan Subrahmanya

Inventor： Tao Cui ,  Feng Lu ,  Anil Kumar Goteti ,  Vignesh Sethuraman ,  Subramanya P. Rao ,  Parvathanathan Subrahmanya

IPC: H04L12/26

CPC classification number: H04W72/1231

Abstract: Various embodiments are disclosed which predict the channel quality indicator (CQI) in High Speed Downlink Packet Access (HSDPA). The accuracy of CQI is crucial for HSDPA performance. In some HSDPA systems the CQI may be as much as three (3) subframes stale. Accordingly, the prediction of CQI values is required in order to efficiently schedule data for transmission over the communication channel. Various embodiments disclose first order adaptive IIR filters which are significantly less complex than the finite impulse response (FIR) counterparts and achieve similar accuracy. By minimizing the mean squared error (MSE), an exact gradient descent algorithm may be used as well as two embodiment pseudolinear regression algorithms.

Abstract translation: 公开了预测高速下行链路分组接入（HSDPA）中的信道质量指示符（CQI）的各种实施例。 对于HSDPA性能，CQI的准确性至关重要。 在一些HSDPA系统中，CQI可能多达三（3）个子帧。 因此，需要CQI值的预测，以便有效地调度通过通信信道传输的数据。 各种实施例公开了比有限脉冲响应（FIR）对应物复杂得多的一阶自适应IIR滤波器，并且实现类似的精度。 通过最小化均方误差（MSE），可以使用精确的梯度下降算法以及两个实施例的伪线性回归算法。

公开(公告)号：US07702001B2

公开(公告)日：2010-04-20

申请号：US10789535

申请日：2004-02-26

Applicant: Roland Reinhard Rick ,  Parvathanathan Subrahmanya ,  Brian K. Butler ,  Shimman Patel ,  Thunyachate Ekvetchavit

Inventor： Roland Reinhard Rick ,  Parvathanathan Subrahmanya ,  Brian K. Butler ,  Shimman Patel ,  Thunyachate Ekvetchavit

IPC: H04B1/707

CPC classification number: H04B1/7085 ,  H04B1/7115 ,  H04B7/0667 ,  H04B7/0697 ,  H04B2201/70701

Abstract: In an antenna diversity environment, the timing offset of the receiver's fingers are based on the timing offset of the received peaks of the base station transmit signals. In a system with non-negligible multipath spacing, the timing offset of the received peaks of the base station transmit signals are not necessarily at the same location. In one embodiment, the demodulating elements for the signal from each base station antenna use the same offset for demodulating and determining an error signal based on pilot signal sampling prior to the timing offset and subsequent to the timing offset. The error signals are averaged and used by a time tracking loop to track the incoming signal. In another embodiment, the demodulating elements for the signal from each base station antenna independently time track the signals with different timing offsets for each finger. The preferred embodiment depends on the method used by the base station to multiplex the data onto multiple transmit antennas.

Abstract translation: 在天线分集环境中，接收机手指的定时偏移基于基站发射信号的接收峰值的定时偏移。 在具有不可忽略的多路径间隔的系统中，基站发射信号的接收峰值的定时偏移不一定在相同的位置。 在一个实施例中，用于来自每个基站天线的信号的解调元件使用相同的偏移量来解调和确定基于在定时偏移之前和定时偏移之后的导频信号采样的误差信号。 误差信号被平均并由时间跟踪环路用于跟踪输入信号。 在另一个实施例中，用于来自每个基站天线的信号的解调元件独立地对每个手指的不同定时偏移时间跟踪信号。 优选实施例取决于基站用于将数据复用到多个发射天线上的方法。

公开(公告)号：US20090325586A1

公开(公告)日：2009-12-31

申请号：US12146232

申请日：2008-06-25

Applicant: Qiang Shen ,  Nathan Yee ,  Parvathanathan Subrahmanya

Inventor： Qiang Shen ,  Nathan Yee ,  Parvathanathan Subrahmanya

IPC: H04W72/00

CPC classification number: H04B1/7107 ,  H04B1/70735 ,  H04B1/71072 ,  H04B2201/70701

Abstract: A mobile station that is configured to perform common channel cancellation may include a parameter estimation unit that is configured to estimate parameters for generating a common channel error. The mobile station may also include a common channel generation unit that is configured to generate the common channel error based on the parameters. The mobile station may also include an adder that is configured to subtract the common channel error from received data samples.

Abstract translation: 被配置为执行公共信道消除的移动站可以包括被配置为估计用于生成公共信道错误的参数的参数估计单元。 移动台还可以包括公共信道生成单元，其被配置为基于参数生成公共信道错误。 移动站还可以包括被配置为从接收的数据样本中减去公共信道误差的加法器。