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：US07986756B2

公开(公告)日：2011-07-26

申请号：US12712924

申请日：2010-02-25

Applicant: Gokhan Mergen ,  Parvathanathan Subrahmanya ,  Vijayaraj Alilaghatta-Kantharaj ,  Nitin Kasturi

Inventor： Gokhan Mergen ,  Parvathanathan Subrahmanya ,  Vijayaraj Alilaghatta-Kantharaj ,  Nitin Kasturi

IPC: H04B1/10

CPC classification number: H04L25/025 ,  H04B17/3913 ,  H04B2201/70701 ,  H04L25/0212 ,  H04L25/0228 ,  H04L25/03038

Abstract: Techniques for filtering noisy estimates to reduce estimation errors are described. A sequence of input values (e.g., for an initial channel impulse response estimate (CIRE)) is filtered with an infinite impulse response (IIR) filter having at least one coefficient to obtain a sequence of output values (e.g., for a filtered CIRE). The coefficient(s) are updated based on the sequence of input values with an adaptive filter, a bank of prediction filters, or a normalized variation technique. To update the coefficient(s) with the adaptive filter, a sequence of predicted values is derived based on the sequence of input values. Prediction errors between the sequence of predicted values and the sequence of input values are determined and filtered to obtain filtered prediction errors. The coefficient(s) of the IIR filter are then updated based on the prediction errors and the filtered prediction errors.

Abstract translation: 描述了用于过滤噪声估计以减少估计误差的技术。 输入值的序列（例如，对于初始信道脉冲响应估计（CIRE））用具有至少一个系数的无限脉冲响应（IIR）滤波器进行滤波以获得输出值序列（例如，对于滤波后的CIRE） 。 基于具有自适应滤波器，预测滤波器组或归一化变化技术的输入值的序列来更新系数。 为了用自适应滤波器更新系数，基于输入值的序列导出预测值序列。 确定并过滤预测值序列与输入值序列之间的预测误差，以获得滤波预测误差。 然后基于预测误差和滤波预测误差来更新IIR滤波器的系数。

公开(公告)号：US20110165907A1

公开(公告)日：2011-07-07

申请号：US13036877

申请日：2011-02-28

Applicant: Erumusele O. Odigie ,  Nitin Kasturi ,  Parvathanathan Subrahmanya

Inventor： Erumusele O. Odigie ,  Nitin Kasturi ,  Parvathanathan Subrahmanya

IPC: H04W52/04

CPC classification number: H04W52/221 ,  H04W52/223 ,  H04W52/267 ,  H04W52/346 ,  H04W52/367 ,  Y02D70/124

Abstract: An apparatus, system, and method efficiently manage transmission power in a user equipment (UE) device by maintaining and applying an authorized power level to determine a transmission power level after a power limited transmission and before a new power control command has been received. The UE device maintains the authorized power level by monitoring and adjusting the authorized power level based on received power control commands. After a power limited transmission where the maximum power level is less than the authorized power level, the UE device determines the transmission power level for the next transmission based on the authorized power level. Accordingly, after the power limiting situation has ceased, the UE device transmits at the optimum power level eliminating the inefficiencies of transmitting at a lower than authorized power before the next power control command is received.

Abstract translation: 一种装置，系统和方法通过维持和应用授权功率电平来有效地管理用户设备（UE）设备中的发射功率，以确定在功率限制传输之后和在接收到新的功率控制命令之前的发射功率电平。 UE设备通过基于接收到的功率控制命令监视和调整授权功率电平来维持授权功率电平。 在最大功率电平小于授权功率电平的功率限制传输之后，UE设备基于授权功率电平确定用于下一次传输的传输功率电平。 因此，在功率限制情况已经停止之后，UE接收到下一个功率控制命令之前，以最佳功率电平发送消除低于授权功率的低效发送的低效率。

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：US20110090946A1

公开(公告)日：2011-04-21

申请号：US12977748

申请日：2010-12-23

Applicant: Gokhan Mergen ,  Parvathanathan Subrahmanya ,  Nitin Kasturi ,  Rajesh Sundaresan

Inventor： Gokhan Mergen ,  Parvathanathan Subrahmanya ,  Nitin Kasturi ,  Rajesh Sundaresan

IPC: H04L27/01

CPC classification number: H04B7/0634 ,  H04B7/0848 ,  H04L7/0058 ,  H04L25/03044

Abstract: Techniques for performing equalization at a receiver are described. In an aspect, equalization is performed by sub-sampling an over-sampled input signal to obtain multiple sub-sampled signals. An over-sampled channel impulse response estimate is derived and sub-sampled to obtain multiple sub-sampled channel impulse response estimates. At least one set of equalizer coefficients is derived based on at least one sub-sampled channel impulse response estimate. At least one sub-sampled signal is filtered with the at least one set of equalizer coefficients to obtain at least one output signal. One sub-sampled signal (e.g., with largest energy) may be selected and equalized based on a set of equalizer coefficients derived from an associated sub-sampled channel impulse response estimate. Alternatively, the multiple sub-sampled signals may be equalized based on multiple sets of equalizer coefficients, which may be derived separately or jointly. The equalizer coefficients may be derived in the time domain or frequency domain

Abstract translation: 描述用于在接收机处执行均衡的技术。 在一方面，通过对过采样输入信号进行子采样来执行均衡以获得多个子采样信号。 导出过采样信道脉冲响应估计并进行子采样以获得多个子采样信道脉冲响应估计。 基于至少一个子采样信道脉冲响应估计导出至少一组均衡器系数。 用至少一组均衡器系数对至少一个子采样信号进行滤波以获得至少一个输出信号。 可以基于从相关联的子采样信道脉冲响应估计导出的一组均衡器系数来选择和均衡一个子采样信号（例如，具有最大能量）。 或者，可以基于可以单独或联合导出的多组均衡器系数来均衡多个子采样信号。 均衡器系数可以在时域或频域中导出

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。