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    Methods and systems for timing acquisition robust to channel fading
    3.
    发明授权
    Methods and systems for timing acquisition robust to channel fading 有权
    定时采集的方法和系统对信道衰落具有鲁棒性

    公开(公告)号：US08249116B2

    公开(公告)日：2012-08-21

    申请号：US12644856

    申请日：2009-12-22

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

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

    IPC分类号： H04J3/06 ,  H04J3/00 ,  H04B7/212

    CPC分类号： H04L27/2662 ,  H04L25/0212 ,  H04L25/0216 ,  H04L27/2695

    摘要： The embodiments provide mechanisms for synchronizing a receiver with OFDM pilots that are robust in the presence of channel fading conditions. In addition to using instantaneous channel estimate values to locate the first arriving path and last arriving path, the methods calculate time-domain averaged channel estimate values and use those averaged values to determine an average first arriving path and last arriving path. A combination of the instantaneous first arriving path and last arriving path and the average first arriving path and last arriving path may then be used to determine the delay spread and calculate a timing offset to be applied in timing synchronization. The various embodiments introduce improvements under channel fading conditions. Time-domain averaging may be embodied in a flexible DSP processor, or implemented in hardware and/or software. Using both instantaneous and time-averaged channel estimates greatly improves the robustness of time synchronization under channel fading conditions.

    摘要翻译： 实施例提供了用于使接收机与在存在信道衰落条件的情况下鲁棒的OFDM导频同步的机制。 除了使用瞬时信道估计值来定位第一到达路径和最后到达路径之外，该方法还计算时域平均信道估计值，并使用这些平均值来确定平均第一到达路径和最后到达路径。 然后可以使用瞬时第一到达路径和最后到达路径以及平均第一到达路径和最后到达路径的组合来确定延迟扩展，并计算要在定时同步中应用的定时偏移。 各种实施例在信道衰落条件下引入改进。 时域平均可以体现在灵活的DSP处理器中，或者在硬件和/或软件中实现。 使用瞬时和时间平均信道估计大大提高了信道衰落条件下时间同步的鲁棒性。

    EXTRACTING INFORMATION FROM POSITIONING PILOT CHANNEL SYMBOLS IN FORWARD LINK ONLY SYSTEM
    4.
    发明申请
    EXTRACTING INFORMATION FROM POSITIONING PILOT CHANNEL SYMBOLS IN FORWARD LINK ONLY SYSTEM 审中-公开
    从前进链接系统中的定位导频信号提取信息

    公开(公告)号：US20100158160A1

    公开(公告)日：2010-06-24

    申请号：US12643664

    申请日：2009-12-21

    申请人： KRISHNA K. MUKKAVILLI ,  Raghuraman Krishnamoorthi ,  Ashok Mantravadi

    发明人： KRISHNA K. MUKKAVILLI ,  Raghuraman Krishnamoorthi ,  Ashok Mantravadi

    IPC分类号： H04L27/06

    CPC分类号： H04L27/2647 ,  H04L25/0212 ,  H04L25/022 ,  H04L25/023

    摘要： Methods, systems, and apparatus, including computer programs encoded on computer readable storage media, for extracting transmitter identification information from the Positioning Pilot Channel (PPC) of a MediaFLO superframe. One of a wide area differentiator (WID) value and a local area differentiator (LID) value associated with the transmitter is determined based on signaling in a first interlace of a symbol received via the PPC. A time domain channel estimate is computed for the PPC based on signaling in a plurality of interlaces of the symbol and also based on the one of the WID and LID values. The time domain channel estimate is used to obtain a frequency domain channel estimate for a second interlace of the symbol that carries the transmitter identification information, and the frequency domain channel estimate is used to determine the transmitter identification information.

    摘要翻译： 方法，系统和装置，包括在计算机可读存储介质上编码的计算机程序，用于从MediaFLO超帧的定位导频信道（PPC）提取发射机识别信息。 基于经由PPC接收的符号的第一交错中的信令来确定与发送器相关联的广域微分器（WID）值和局部区域微分器（LID）值之一。 基于符号的多个交织中的信令，并且还基于WID和LID值中的一个来计算PPC的时域信道估计。 使用时域信道估计来获得携带发射机识别信息的符号的第二交错的频域信道估计，并且使用频域信道估计来确定发射机识别信息。

    METHODS AND SYSTEMS FOR TIMING ACQUISITION ROBUST TO CHANNEL FADING
    5.
    发明申请
    METHODS AND SYSTEMS FOR TIMING ACQUISITION ROBUST TO CHANNEL FADING 有权
    用于定时采集的方法和系统对信道渐弱的鲁棒性

    公开(公告)号：US20100246564A1

    公开(公告)日：2010-09-30

    申请号：US12644856

    申请日：2009-12-22

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

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

    IPC分类号： H04J3/06 ,  H04L27/28

    CPC分类号： H04L27/2662 ,  H04L25/0212 ,  H04L25/0216 ,  H04L27/2695

    摘要： The embodiments provide mechanisms for synchronizing a receiver with OFDM pilots that are robust in the presence of channel fading conditions. In addition to using instantaneous channel estimate values to locate the first arriving path and last arriving path, the methods calculate time-domain averaged channel estimate values and use those averaged values to determine an average first arriving path and last arriving path. A combination of the instantaneous first arriving path and last arriving path and the average first arriving path and last arriving path may then be used to determine the delay spread and calculate a timing offset to be applied in timing synchronization. The various embodiments introduce improvements under channel fading conditions. Time-domain averaging may be embodied in a flexible DSP processor, or implemented in hardware and/or software. Using both instantaneous and time-averaged channel estimates greatly improves the robustness of time synchronization under channel fading conditions.

    摘要翻译： 实施例提供了用于使接收机与存在信道衰落条件时鲁棒的OFDM导频同步的机制。 除了使用瞬时信道估计值来定位第一到达路径和最后到达路径之外，该方法还计算时域平均信道估计值，并使用这些平均值来确定平均第一到达路径和最后到达路径。 然后可以使用瞬时第一到达路径和最后到达路径以及平均第一到达路径和最后到达路径的组合来确定延迟扩展，并计算要在定时同步中应用的定时偏移。 各种实施例在信道衰落条件下引入改进。 时域平均可以体现在灵活的DSP处理器中，或者在硬件和/或软件中实现。 使用瞬时和时间平均信道估计大大提高了信道衰落条件下时间同步的鲁棒性。

    Methods and apparatus for timing synchronization based on transitional pilot symbols
    8.
    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。