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    Wide area and local network ID transmission for communication systems
    23.
    发明授权
    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：US07852822B2

    公开(公告)日：2010-12-14

    申请号：US11021310

    申请日：2004-12-22

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

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

    IPC分类号： H04J1/00

    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。

    Fine timing acquisition
    27.
    发明申请
    Fine timing acquisition 审中-公开
    精细定时采集

    公开(公告)号：US20060221810A1

    公开(公告)日：2006-10-05

    申请号：US11372394

    申请日：2006-03-08

    申请人： Bojan Vrcelj ,  Fuyun Ling ,  Raghuraman Krishnamoorthi ,  Vinay Murthy

    发明人： Bojan Vrcelj ,  Fuyun Ling ,  Raghuraman Krishnamoorthi ,  Vinay Murthy

    IPC分类号： H04J11/00 ,  H04J3/06

    CPC分类号： H04L27/2656 ,  H04L27/2663 ,  H04L27/2665 ,  H04L27/2675 ,  H04L27/2695

    摘要： A method for synchronizing timing of a receiver to a received orthogonal frequency division multiplexing (OFDM) signal is disclosed. A first timing acquisition is performed with a first received time division multiplexed (TDM) pilot to determine a course timing estimate of the received OFDM signal. A second timing acquisition is performed with a second TDM pilot to determine a fine timing estimate for a OFDM symbol of the received OFDM signal. In the second timing acquisition, the accumulated energy of channel taps over a detection window is determined and a trailing edge of the accumulated energy curve is detected. A Fourier transform (FT) collection window location for subsequent OFDM symbols is adjusted according to the trailing edge information.

    摘要翻译： 公开了一种用于使接收机的定时与接收的正交频分复用（OFDM）信号同步的方法。 利用第一接收时分复用（TDM）导频执行第一定时获取，以确定所接收的OFDM信号的路线定时估计。 用第二TDM导频执行第二定时获取，以确定接收到的OFDM信号的OFDM符号的精确定时估计。 在第二定时获取中，确定在检测窗口上的通道抽头的累积能量，并且检测累积能量曲线的后沿。 根据后沿信息调整后续OFDM符号的傅立叶变换（FT）收集窗口位置。

    Efficient employment of digital upsampling using IFFT in OFDM systems for simpler analog filtering
    28.
    发明授权
    Efficient employment of digital upsampling using IFFT in OFDM systems for simpler analog filtering 有权
    在OFDM系统中有效利用使用IFFT的数字上采样进行更简单的模拟滤波

    公开(公告)号：US09042461B2

    公开(公告)日：2015-05-26

    申请号：US11373001

    申请日：2006-03-09

    申请人： Raghuraman Krishnamoorthi ,  Fuyun Ling ,  Rajiv Vijayan

    发明人： Raghuraman Krishnamoorthi ,  Fuyun Ling ,  Rajiv Vijayan

    IPC分类号： H04N7/18 ,  H04L27/26

    CPC分类号： H04L27/2644

    摘要： Systems and methods are provided for transmitting OFDM information via IFFT up-sampling components that transmit data at a higher sampling rate than conventional systems to simplify filter requirements and mitigate leakage between symbols. In one embodiment, an NL point IFFT is performed on a zero inserted set of frequency domain symbols. In another embodiment, the NL point IFFT is further optimized by exploiting the fact that (N−1) L of the frequency domain symbols are zero. This enables an embodiment that consists of a pre-processor that multiplies the input samples by complex phase factors, followed by L point IFFTs.

    摘要翻译： 提供了系统和方法，用于通过IFFT上采样组件传输OFDM信息，该组件以比常规系统更高的采样速率传输数据，以简化滤波器要求并减轻符号之间的泄漏。 在一个实施例中，对零插入的频域符号组执行NL点IFFT。 在另一个实施例中，通过利用频域符号的（N-1）L为零的事实进一步优化NL点IFFT。 这使得能够由预处理器组成的实施例，该预处理器将输入样本乘以复相位因子，随后是L点IFFT。

    Efficient employment of digital upsampling using IFFT in OFDM systems for simpler analog filtering
    29.
    发明申请
    Efficient employment of digital upsampling using IFFT in OFDM systems for simpler analog filtering 有权
    在OFDM系统中有效利用使用IFFT的数字上采样进行更简单的模拟滤波

    公开(公告)号：US20060215540A1

    公开(公告)日：2006-09-28

    申请号：US11373001

    申请日：2006-03-09

    申请人： Raghuraman Krishnamoorthi ,  Fuyun Ling ,  Rajiv Vijayan

    发明人： Raghuraman Krishnamoorthi ,  Fuyun Ling ,  Rajiv Vijayan

    IPC分类号： H04J11/00

    CPC分类号： H04L27/2644

    摘要： Systems and methods are provided for transmitting OFDM information via IFFT up-sampling components that transmit data at a higher sampling rate than conventional systems to simplify filter requirements and mitigate leakage between symbols. In one embodiment, an NL point IFFT is performed on a zero inserted set of frequency domain symbols. In another embodiment, the NL point IFFT is further optimized by exploiting the fact that (N−1) L of the frequency domain symbols are zero. This enables an embodiment that consists of a pre-processor that multiplies the input samples by complex phase factors, followed by L point IFFTs.

    摘要翻译： 提供了系统和方法，用于通过IFFT上采样组件传输OFDM信息，该组件以比常规系统更高的采样速率传输数据，以简化滤波器要求并减轻符号之间的泄漏。 在一个实施例中，对零插入的频域符号组执行NL点IFFT。 在另一个实施例中，通过利用频域符号的（N-1）L为零的事实进一步优化NL点IFFT。 这使得能够由预处理器组成的实施例，该预处理器将输入样本乘以复相位因子，随后是L点IFFT。