公开(公告)号：US08514984B2

公开(公告)日：2013-08-20

申请号：US12563655

申请日：2009-09-21

Applicant: Jia Tang ,  Atul A. Salvekar ,  Parvathanathan Subrahmanya ,  Andrew Sendonaris ,  Shantanu Khare ,  Jong Hyeon Park ,  Brian C. Banister ,  Tao Cui

Inventor： Jia Tang ,  Atul A. Salvekar ,  Parvathanathan Subrahmanya ,  Andrew Sendonaris ,  Shantanu Khare ,  Jong Hyeon Park ,  Brian C. Banister ,  Tao Cui

IPC: H04L27/06

CPC classification number: H04L1/005 ,  H04L1/06 ,  H04L1/1812 ,  H04L1/1829 ,  H04L25/0204 ,  H04L25/023 ,  H04L25/0244

Abstract: Certain aspects of the present disclosure relate to a method for iterative decoding with re-transmissions of data and to a method for iterative decoding with soft decision directed channel estimation.

Abstract translation: 本公开的某些方面涉及用于重新传输数据的迭代解码的方法以及用于通过软判决定向信道估计进行迭代解码的方法。

公开(公告)号：US20130070869A1

公开(公告)日：2013-03-21

申请号：US13237868

申请日：2011-09-20

Applicant: Mariam Motamed ,  Alexei Yurievitch Gorokhov ,  Mike L. Mccloud ,  Parvathanathan Subrahmanya

Inventor： Mariam Motamed ,  Alexei Yurievitch Gorokhov ,  Mike L. Mccloud ,  Parvathanathan Subrahmanya

IPC: H04L27/06 ,  H04L27/00

CPC classification number: H04L5/0051 ,  H04L25/0212 ,  H04L25/0224

Abstract: Estimating a channel impulse response (CIR) for a wireless transmission, for example a multimedia broadcast multicast services single frequency network (MBSFN) transmission, may be performed by a receiver of an wireless subframe, without requiring operational memory in excess of what is needed for CIR estimation of unicast signaling, while providing enhanced delay spread coverage. The wireless subframe may be a MBSFN subframe. The receiver may form an aggregate vector of pilot tones extracted from an OFDM reference symbol of an wireless subframe. The receiver may subsample the aggregate vector to obtain a plurality of sub-vectors each comprising a distinct subsampling phase. The receiver may process the plurality of sub-vectors using an inverse fast Fourier transform to obtain time domain representations of each of the sub-vectors. The receiver may combine the time domain representations in various ways to obtain a CIR estimate for the wireless subframe.

Abstract translation: 估计用于无线传输的信道脉冲响应（CIR），例如多媒体广播多播服务单频网（MBSFN）传输，可以由无线子帧的接收机执行，而不需要超过所需的操作存储器 CIR估计单播信令，同时提供增强的延迟扩展覆盖。 无线子帧可以是MBSFN子帧。 接收机可以形成从无线子帧的OFDM参考符号提取的导频音的聚合向量。 接收机可以对聚合向量进行子采样以获得每个包括不同子采样相位的多个子向量。 接收机可以使用快速傅里叶逆变换处理多个子向量，以获得每个子向量的时域表示。 接收机可以以各种方式组合时域表示以获得无线子帧的CIR估计。

公开(公告)号：US20120224498A1

公开(公告)日：2012-09-06

申请号：US13040824

申请日：2011-03-04

Applicant: Farrokh Abrishamkar ,  Miriam Motamed ,  Ali Yazdan Panah ,  Parvathanathan Subrahmanya ,  Amir Farajidana ,  Dinesh Krithivasan ,  Kenneth Kreutz-Delgado

Inventor： Farrokh Abrishamkar ,  Miriam Motamed ,  Ali Yazdan Panah ,  Parvathanathan Subrahmanya ,  Amir Farajidana ,  Dinesh Krithivasan ,  Kenneth Kreutz-Delgado

IPC: H04L12/26

CPC classification number: H04L25/0204 ,  H04L25/0228 ,  H04L25/0242

Abstract: Certain aspects of the present disclosure propose a method for estimating a channel utilizing Sparse Bayesian Learning (SBL) algorithm. The proposed method employs a Basis expansion (e.g., polynomial) channel model, and iteratively performs SBL algorithm to adjust parameters of the channel model.

Abstract translation: 本公开的某些方面提出了一种利用稀疏贝叶斯学习（SBL）算法来估计信道的方法。 所提出的方法采用基础扩展（例如，多项式）信道模型，并且迭代地执行SBL算法来调整信道模型的参数。

公开(公告)号：US08170084B2

公开(公告)日：2012-05-01

申请号：US13216779

申请日：2011-08-24

Applicant: Parvathanathan Subrahmanya ,  Thejaswi Bharadwaj Madapushi Sheshadri ,  Vivek Chawla

Inventor： Parvathanathan Subrahmanya ,  Thejaswi Bharadwaj Madapushi Sheshadri ,  Vivek Chawla

IPC: H04B1/00

CPC classification number: H04L27/2278 ,  H04B1/7085 ,  H04B2201/70709 ,  H04L2027/003 ,  H04L2027/0034 ,  H04L2027/0065 ,  H04W52/0229 ,  Y02D70/122 ,  Y02D70/1242 ,  Y02D70/166 ,  Y02D70/24 ,  Y02D70/40

Abstract: Quick frequency tracking (QFT), quick time tracking (QTT), and non-causal pilot filtering (NCP) are used to detect sporadically transmitted signaling, e.g., paging indicators. For QFT, multiple hypothesized frequency errors are applied to an input signal to obtain multiple rotated signals. The energies of the rotated signals are computed. The hypothesized frequency error with the largest energy is provided as a frequency error estimate. For QTT, coherent accumulation is performed on the input signal for a first set of time offsets, e.g., early, on-time, and late. Interpolation, energy computation, and non-coherent accumulation are then performed to obtain a timing error estimate with higher time resolution. For NCP, pilot symbols are filtered with a non-causal filter to obtain pilot estimates for one antenna for non-STTD and for two antennas for STTD. The frequency and timing error estimates and the pilot estimates are used to detect the signaling.

Abstract translation: 使用快速频率跟踪（QFT），快速时间跟踪（QTT）和非因果导频滤波（NCP）来检测偶发地发送的信令，例如寻呼指示符。 对于QFT，将多个假设频率误差应用于输入信号以获得多个旋转信号。 计算旋转信号的能量。 提供具有最大能量的假设频率误差作为频率误差估计。 对于QTT，对于第一组时间偏移的输入信号执行相干累加，例如早，时，晚。 然后执行插值，能量计算和非相干累加，以获得具有更高时间分辨率的定时误差估计。 对于NCP，使用非因果滤波器对导频符号进行滤波，以获得用于非STTD的一个天线和用于STTD的两个天线的导频估计。 频率和定时误差估计和导频估计用于检测信令。

公开(公告)号：US20110306315A1

公开(公告)日：2011-12-15

申请号：US13216779

申请日：2011-08-24

Applicant: Parvathanathan Subrahmanya ,  Thejaswi Bharadwaj Madapushi Sheshadri ,  Vivek Chawla

Inventor： Parvathanathan Subrahmanya ,  Thejaswi Bharadwaj Madapushi Sheshadri ,  Vivek Chawla

IPC: H04B17/00

CPC classification number: H04L27/2278 ,  H04B1/7085 ,  H04B2201/70709 ,  H04L2027/003 ,  H04L2027/0034 ,  H04L2027/0065 ,  H04W52/0229 ,  Y02D70/122 ,  Y02D70/1242 ,  Y02D70/166 ,  Y02D70/24 ,  Y02D70/40

Abstract: Quick frequency tracking (QFT), quick time tracking (QTT), and non-causal pilot filtering (NCP) are used to detect sporadically transmitted signaling, e.g., paging indicators. For QFT, multiple hypothesized frequency errors are applied to an input signal to obtain multiple rotated signals. The energies of the rotated signals are computed. The hypothesized frequency error with the largest energy is provided as a frequency error estimate. For QTT, coherent accumulation is performed on the input signal for a first set of time offsets, e.g., early, on-time, and late. Interpolation, energy computation, and non-coherent accumulation are then performed to obtain a timing error estimate with higher time resolution. For NCP, pilot symbols are filtered with a non-causal filter to obtain pilot estimates for one antenna for non-STTD and for two antennas for STTD. The frequency and timing error estimates and the pilot estimates are used to detect the signaling.

Abstract translation: 使用快速频率跟踪（QFT），快速时间跟踪（QTT）和非因果导频滤波（NCP）来检测偶发地发送的信令，例如寻呼指示符。 对于QFT，将多个假设频率误差应用于输入信号以获得多个旋转信号。 计算旋转信号的能量。 提供具有最大能量的假设频率误差作为频率误差估计。 对于QTT，对于第一组时间偏移的输入信号执行相干累加，例如早，时，晚。 然后执行插值，能量计算和非相干累加，以获得具有更高时间分辨率的定时误差估计。 对于NCP，使用非因果滤波器对导频符号进行滤波，以获得用于非STTD的一个天线和用于STTD的两个天线的导频估计。 频率和定时误差估计和导频估计用于检测信令。

公开(公告)号：US07903633B2

公开(公告)日：2011-03-08

申请号：US12196489

申请日：2008-08-22

Applicant: Francesco Grilli ,  Charles E. Wheatley, III ,  Serge D. Willenegger ,  Parvathanathan Subrahmanya

Inventor： Francesco Grilli ,  Charles E. Wheatley, III ,  Serge D. Willenegger ,  Parvathanathan Subrahmanya

IPC: H04J3/06

CPC classification number: H04W56/002 ,  H04B7/2668 ,  H04B2201/70702 ,  H04W56/001 ,  H04W56/0015 ,  H04W56/0045 ,  H04W92/20

Abstract: Schemes to time-align transmissions from multiple base stations to a terminal. To achieve time-alignment, differences between the arrival times of transmissions from the base stations, as observed at the terminal, are determined and provided to the system and used to adjust the timing at the base stations such that terminal-specific radio frames arrive at the terminal within a particular time window. In one scheme, a time difference between two base stations is partitioned into a frame-level time difference and a chip-level time difference. Whenever requested to perform and report time difference measurements, the terminal measures the chip-level timing for each candidate base station relative to a reference base station. Additionally, the terminal also measures the frame-level timing and includes this information in the time difference measurement only if required. Otherwise, the terminal sets the frame-level part to a predetermined value (e.g., zero).

Abstract translation: 将来自多个基站的传输时间对齐到终端的方案。 为了实现时间对准，确定在终端观察到的来自基站的传输的到达时间之间的差异，并将其提供给系统，并用于调整基站处的定时，使得终端专用无线帧到达 终端在特定的时间窗口内。 在一个方案中，两个基站之间的时差被划分为帧级时间差和码片级时间差。 无论何时请求执行和报告时差测量，终端测量每个候选基站相对于参考基站的芯片级定时。 此外，终端还测量帧级定时，并且仅在需要时在时差测量中包括该信息。 否则，终端将帧级部分设置为预定值（例如，零）。

公开(公告)号：US20100309900A1

公开(公告)日：2010-12-09

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: H04B7/216

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：US20100232397A1

公开(公告)日：2010-09-16

申请号：US12404203

申请日：2009-03-13

Applicant: An-Swol Clement Hu ,  Jittra Jootar ,  Parvathanathan Subrahmanya

Inventor： An-Swol Clement Hu ,  Jittra Jootar ,  Parvathanathan Subrahmanya

IPC: H04J3/00 ,  H04W72/12

CPC classification number: H04B1/7083 ,  H04B1/70735

Abstract: A method and apparatus for improved initial cell acquisition with reduced frequency error impact. The method determines the slot timing of a transmission, identifies the primary scrambling code and frame timing using the common pilot channel, and provides a path profile using a pseudorandom noise (PN) search. An apparatus using a cell searcher that performs the method is also described.

Abstract translation: 一种用于改善初始细胞获取并减少频率误差影响的方法和装置。 该方法确定传输的时隙定时，使用公共导频信道识别主扰码和帧定时，并且使用伪随机噪声（PN）搜索来提供路径简档。 还描述了使用执行该方法的小区搜索器的装置。

公开(公告)号：US07730381B2

公开(公告)日：2010-06-01

申请号：US10875107

申请日：2004-06-09

Applicant: Amit Butala ,  Parvathanathan Subrahmanya ,  Hyukjun Oh

Inventor： Amit Butala ,  Parvathanathan Subrahmanya ,  Hyukjun Oh

IPC: H03M13/00

CPC classification number: H04W52/04 ,  H04L1/20 ,  H04L1/201 ,  H04W52/12 ,  H04W52/16 ,  H04W52/20 ,  H04W52/287 ,  H04W52/362 ,  H04W52/44

Abstract: Erasure detection and power control are performed for an intermittently active transport channel with unknown format. A receiver processes each received block and determines whether it passes or fails CRC. For each received block with CRC failure, the receiver performs erasure detection by computing a symbol error rate (SER) and energy of the received block, comparing the computed SER against an SER threshold, comparing the computed energy against an energy threshold, and declaring an erasure if the computed SER is less than the SER threshold and the computed energy exceeds the energy threshold. The SER and energy thresholds may be adjusted based on the average SER and the average energy for prior received blocks with CRC failures. For power control, an SIR target is increased by an UP step whenever an erased block is detected for the transport channel.

Abstract translation: 对具有未知格式的间歇活动的传输信道执行擦除检测和功率控制。 接收器处理每个接收的块并确定其是否通过或失败CRC。 对于每个具有CRC故障的接收块，接收机通过计算接收块的符号错误率（SER）和能量来执行擦除检测，将计算的SER与SER阈值进行比较，将计算出的能量与能量阈值进行比较，并且声明 如果计算的SER小于SER阈值并且计算的能量超过能量阈值，则擦除。 可以基于具有CRC故障的先前接收的块的平均SER和平均能量来调整SER和能量阈值。 对于功率控制，每当检测到用于传输信道的擦除块时，SIR目标通过UP步增加。

公开(公告)号：US07454209B2

公开(公告)日：2008-11-18

申请号：US10632411

申请日：2003-08-01

Applicant: Parvathanathan Subrahmanya

Inventor： Parvathanathan Subrahmanya

IPC: H04Q7/20 ,  H04B1/00 ,  H04B1/10

CPC classification number: H04L25/0214 ,  H04B1/7115 ,  H04B2201/70701 ,  H04L25/0228

Abstract: A method and apparatus are provided for adapting a pilot filter based on the velocity of a wireless communication device (WCD) in relation to a wireless network infrastructure. The pilot filter is adapted by determining pilot coefficients for the pilot filter based on the WCD velocity. The pilot filter may be located in the WCD, or in the network infrastructure, or in both.

Abstract translation: 提供了一种用于根据无线通信设备（WCD）相对于无线网络基础设施的速度来适配导频滤波器的方法和装置。 通过基于WCD速度确定导频滤波器的导频系数来适配导频滤波器。 导频滤波器可以位于WCD中，或者位于网络基础设施中，或两者中。