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    Wide area and local network ID transmission for communication systems
    3.
    发明申请
    Wide area and local network ID transmission for communication systems 有权
    通信系统的广域和本地网络ID传输

    公开(公告)号：US20060133388A1

    公开(公告)日：2006-06-22

    申请号：US11021310

    申请日：2004-12-22

    申请人： Michael Wang ,  Bojan Vrcelj ,  Krishna Mukkavilli ,  Raghuraman Krishnamoorthi ,  Rajiv Vijayan

    发明人： Michael Wang ,  Bojan Vrcelj ,  Krishna Mukkavilli ,  Raghuraman Krishnamoorthi ,  Rajiv Vijayan

    IPC分类号： H04L12/56

    CPC分类号： H04L5/0048 ,  H04L5/0007 ,  H04L5/0083 ,  H04L27/261

    摘要： The embodiments utilize OFDM symbols to communicate network IDs. The IDs are encoded into symbols utilizing the network IDs as seeds to scramble respective pilots that are then transmitted by utilizing the symbols. The pilots can be structured into a single OFDM symbol and/or multiple OFDM symbols. The single symbol structure for transmitting the network IDs is independent of the number of network ID bits and minimizes frequency offset and Doppler effects. The multiple symbol structure allows a much coarser timing accuracy to be employed at the expense of transmitting additional symbols. Several embodiments employ a search function to find possible network ID candidates from a transmitted symbol and a selection function to find an optimum candidate from a network ID candidate list.

    摘要翻译： 这些实施例利用OFDM符号来传送网络ID。 ID被编码成使用网络ID作为种子的符号，以对通过利用符号进行发送的各个导频进行加扰。 导频可以被构造成单个OFDM符号和/或多个OFDM符号。 用于发送网络ID的单个符号结构与网络ID比特数无关，并且使频偏和多普勒效应最小化。 多符号结构允许以牺牲传输附加符号为代价采用更粗糙的定时精度。 几个实施例采用搜索功能来从发送的符号和选择功能中找到可能的网络ID候选，以从网络ID候选列表中找到最佳候选。

    METHODS AND APPARATUS FOR TIME TRACKING USING ASSITANCE FROM TDM PILOTS IN A COMMUNICATION NETWORK
    6.
    发明申请
    METHODS AND APPARATUS FOR TIME TRACKING USING ASSITANCE FROM TDM PILOTS IN A COMMUNICATION NETWORK 有权
    在通信网络中使用TDM PILOTS的资产进行时间跟踪的方法和装置

    公开(公告)号：US20110116396A1

    公开(公告)日：2011-05-19

    申请号：US12917789

    申请日：2010-11-02

    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： H04J3/14 ,  H04L12/26

    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
    9.
    发明申请
    METHODS AND APPARATUS FOR TIMING SYNCHRONIZATION BASED ON TRANSITIONAL PILOT SYMBOLS 有权
    基于过渡引导符号的时序同步的方法与装置

    公开(公告)号：US20080165908A1

    公开(公告)日：2008-07-10

    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： H04L7/00

    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。

    Methods and systems for timing acquisition robust to channel fading
    10.
    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。