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    METHODS AND APPARATUS FOR TIME TRACKING USING ASSISTANCE FROM TDM PILOTS IN A COMMUNICATION NETWORK
    21.
    发明申请
    METHODS AND APPARATUS FOR TIME TRACKING USING ASSISTANCE FROM TDM PILOTS IN A COMMUNICATION NETWORK 有权
    在通信网络中使用TDM PILOTS协助进行时间跟踪的方法和装置

    公开(公告)号：US20080260008A1

    公开(公告)日：2008-10-23

    申请号：US11970381

    申请日：2008-01-07

    申请人： Bojan Vrcelj ,  Ashok Mantravadi ,  Krishna Kiran Mukkavilli ,  Raghuraman Krishnamoorthi

    发明人： Bojan Vrcelj ,  Ashok Mantravadi ,  Krishna Kiran Mukkavilli ,  Raghuraman Krishnamoorthi

    IPC分类号： H04B1/707

    CPC分类号： H04L27/2662 ,  H04L25/0216 ,  H04L25/0224 ,  H04L27/2675 ,  H04L27/2695

    摘要： Methods and apparatus for time tracking using assistance from TDM pilots in a communication network. In an aspect, a method is provided for time tracking in a device operating on a communication network, wherein the device performs a time tracking algorithm. The method includes determining a delay spread, and modifying at least one parameter used by the time tracking algorithm based on the delay spread. In another aspect, an apparatus is provided for time tracking in a device operating on a communication network, wherein the device performs a time tracking algorithm. The apparatus includes computation logic for determining a delay spread, and control logic for modifying at least one parameter used by the time tracking algorithm based on the delay spread.

    摘要翻译： 在通信网络中使用TDM导频协助进行时间跟踪的方法和装置。 在一方面，提供了一种用于在通信网络上操作的设备中进行时间跟踪的方法，其中该设备执行时间跟踪算法。 该方法包括确定延迟扩展，以及基于延迟扩展修改由时间跟踪算法使用的至少一个参数。 在另一方面，提供了一种用于在通信网络上操作的设备中进行时间跟踪的设备，其中该设备执行时间跟踪算法。 该装置包括用于确定延迟扩展的计算逻辑，以及用于基于延迟扩展修改由时间跟踪算法使用的至少一个参数的控制逻辑。

    Methods and apparatus for timing synchronization based on transitional pilot symbols
    22.
    发明授权
    Methods and apparatus for timing synchronization based on transitional pilot symbols 有权
    基于过渡导频符号的定时同步的方法和装置

    公开(公告)号：US09008198B2

    公开(公告)日：2015-04-14

    申请号：US11765428

    申请日：2007-06-19

    申请人： Bojan Vrcelj ,  Krishna Kiran Mukkavilli ,  Ashok Mantravadi ,  Raghuraman Krishnamoorthi

    发明人： Bojan Vrcelj ,  Krishna Kiran Mukkavilli ,  Ashok Mantravadi ,  Raghuraman Krishnamoorthi

    IPC分类号： H04K1/10 ,  H04L27/28 ,  H04L27/26 ,  H04L5/00 ,  H04L7/08 ,  H04L25/02

    CPC分类号： H04L27/2662 ,  H04L5/0048 ,  H04L7/08 ,  H04L25/0216 ,  H04L25/023 ,  H04L27/2613 ,  H04L27/2675 ,  H04L27/2695

    摘要： Methods and apparatus for timing synchronization based on transitional pilot symbols. In an aspect, a method is provided for time tracking synchronization in an OFDM system. The method includes receiving at least one TDM pilot symbol comprising a plurality of modulated sub-carriers that are configured to provide a channel estimate having a length that extends up to a duration of an FFT used for data transmission. The method also includes determining one or both of an instantaneous and averaged channel estimates from the plurality of modulated sub-carriers, and calculating a timing offset based on one or both of the channel estimates. An apparatus includes a receiver configured to receive the at least one TDM pilot symbol, a channel estimator configured to determine the instantaneous and averaged channel estimates, and a time synchronizer configured to calculate a timing offset based on the channel estimates.

    摘要翻译： 基于过渡导频符号的定时同步的方法和装置。 在一方面，提供了一种用于OFDM系统中的时间跟踪同步的方法。 该方法包括：接收至少一个TDM导频符号，该TDM导频符号包括多个经调制的子载波，其被配置为提供具有延伸到用于数据传输的FFT的持续时间的长度的信道估计。 该方法还包括确定来自多个调制子载波的瞬时和平均信道估计中的一个或两个，以及基于信道估计中的一个或两个来计算定时偏移。 一种装置包括被配置为接收所述至少一个TDM导频符号的接收机，被配置为确定瞬时和平均信道估计的信道估计器，以及被配置为基于信道估计来计算定时偏移的时间同步器。

    ADAPTIVE THRESHOLDING FOR OFDM CHANNEL ESTIMATION
    24.
    发明申请
    ADAPTIVE THRESHOLDING FOR OFDM CHANNEL ESTIMATION 有权
    OFDM信道估计的自适应阈值

    公开(公告)号：US20100002785A1

    公开(公告)日：2010-01-07

    申请号：US12250135

    申请日：2008-10-13

    申请人： Ashok Mantravadi ,  Krishna Kiran Mukkavilli ,  Raghuraman Krishnamoorthi ,  Rajeev Krishnamurthi

    发明人： Ashok Mantravadi ,  Krishna Kiran Mukkavilli ,  Raghuraman Krishnamoorthi ,  Rajeev Krishnamurthi

    IPC分类号： H04L27/28

    CPC分类号： H04L25/0218 ,  H04L5/0007 ,  H04L25/0204 ,  H04L25/022 ,  H04L25/0224

    摘要： An adaptive thresholding technique eliminates suboptimum threshold values by adjusting for varying channel conditions to eliminate interference where no channel energy is present, without discarding viable taps having useful channel energy. The adaptive thresholding technique adaptively optimizes receive threshold values for both wide and local area channels based only on measured C/I ratios 300. Thresholds are calculated based on instantaneous C/I estimates and/or weighted average C/I estimates calculated from WID/LID energies obtained from the current superframe WIC/LIC symbols respectively. In alternate embodiments, thresholds are calculated based on instantaneous C/I estimates and/or weighted average C/I estimates calculated from WTPC and LTPC symbols for the wide and local area channels, respectively The present adaptive thresholding technique dynamically reduces the threshold as the C/I estimate increases to mitigate performance degradation due to removal of weak signal taps. There is a separate threshold for each of the 12 coding and modulation modes supported by an exemplary receiver.

    摘要翻译： 自适应阈值技术通过调整不同的信道条件来消除次优阈值，以消除不存在信道能量的干扰，而不丢弃具有有用信道能量的可行分接头。 自适应阈值技术仅基于测量的C / I比300自适应地优化宽和局域信道的接收阈值。阈值基于从WID / LID计算的瞬时C / I估计和/或加权平均C / I估计来计算 从当前超帧WIC / LIC符号获得的能量。 在替代实施例中，基于针对宽和局域信道的WTPC和LTPC符号计算的瞬时C / I估计和/或加权平均C / I估计来计算阈值。当前自适应阈值技术动态地将阈值设置为C /我估计增加以减轻由于去除弱信号抽头而导致的性能下降。 对于由示例性接收机支持的12个编码和调制模式中的每一个，存在单独的阈值。

    METHODS AND APPARATUS FOR TRANSMITTER IDENTIFICATION IN A WIRELESS NETWORK
    25.
    发明申请
    METHODS AND APPARATUS FOR TRANSMITTER IDENTIFICATION IN A WIRELESS NETWORK 审中-公开
    无线网络中发射机识别的方法和设备

    公开(公告)号：US20090028100A1

    公开(公告)日：2009-01-29

    申请号：US11834654

    申请日：2007-08-06

    申请人： Krishna Kiran Mukkavilli ,  Ashok Mantravadi ,  Raghuraman Krishnamoorthi ,  Murali Ramaswamy Chari

    发明人： Krishna Kiran Mukkavilli ,  Ashok Mantravadi ,  Raghuraman Krishnamoorthi ,  Murali Ramaswamy Chari

    IPC分类号： H04Q7/00 ,  H04L27/28

    CPC分类号： H04L5/0007 ,  H04L5/0048 ,  H04L25/0224 ,  H04L27/2613

    摘要： Methods and apparatus for transmitter identification in a wireless network are disclosed. In an example, a method is provided that encodes pilot information on a first portion of a number of subcarriers in a symbol within a pilot positioning channel for an active transmitter. The method further includes encoding transmitter identification information on a second dedicated portion of the number of subcarriers of the symbol. The method also encompasses including a transmitter allocation field that signals the number of succeeding symbols that will be used by the transmitter for transmitting any other information in an interference free manner. In another example, a method is provided that receives a symbol having a number of subcarriers from a transmitter. A channel estimate and an energy measurement of the symbol using a first portion of the subcarriers. A dedicated second portion of the number of subcarriers in the symbol are then decoded to determine the transmitter identification information.

    摘要翻译： 公开了用于无线网络中的发射机识别的方法和装置。 在一个示例中，提供了一种方法，其对于有源发射机的导频定位信道内的符号中的多个子载波的第一部分上的导频信息进行编码。 该方法还包括在符号的子载波数的第二专用部分上编码发射机识别信息。 该方法还包括发射机分配字段，其指示将由干扰自由方式发送用于发送任何其它信息的发射机将使用的后续符号的数量。 在另一示例中，提供了一种从发射机接收具有多个子载波的符号的方法。 使用子载波的第一部分的信号估计和符号的能量测量。 然后对符号中的子载波数量的专用第二部分进行解码以确定发射机识别信息。

    Methods and apparatus for adapting channel estimation in a communication system
    27.
    发明授权
    Methods and apparatus for adapting channel estimation in a communication system 有权
    在通信系统中适应信道估计的方法和装置

    公开(公告)号：US08259865B2

    公开(公告)日：2012-09-04

    申请号：US12396144

    申请日：2009-03-02

    申请人： Raghuraman Krishnamoorthi ,  Krishna Kiran Mukkavilli ,  Ashok Mantravadi

    发明人： Raghuraman Krishnamoorthi ,  Krishna Kiran Mukkavilli ,  Ashok Mantravadi

    IPC分类号： H04L27/06

    CPC分类号： H04L25/0202

    摘要： Methods and apparatus for adapting a channel estimation scheme in a transceiver in a communication system are disclosed to adapt channel estimation to the transceiver environment, particularly for high Doppler environments. The disclosed methods and apparatus effect determination of an estimate of a power delay profile of a channel or a time correlation of the channel, or both. A channel estimation scheme is then determined based on at least one of the determined power delay profile and time correlation of the channel. By basing determination of a channel estimation scheme on the power delay profile and/or the time correlation of the channel, the channel estimation scheme is adapted to the particular environment of the transceiver by accounting for the delay spread of the channel and/or the speed of the transceiver.

    摘要翻译： 公开了用于在通信系统中的收发器中适配信道估计方案的方法和装置，以使信道估计适应收发器环境，特别是对于高多普勒环境。 所公开的方法和装置效应确定信道的功率延迟分布的估计或信道的时间相关性，或两者。 然后基于所确定的功率延迟分布和信道的时间相关性中的至少一个来确定信道估计方案。 通过基于信道估计方案对功率延迟分布的确定和/或信道的时间相关性，信道估计方案通过考虑信道的延迟扩展和/或速度来适应收发器的特定环境 的收发器。