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    Local and wide-area transmissions in a wireless broadcast network
    61.
    发明授权
    Local and wide-area transmissions in a wireless broadcast network 有权
    无线广播网络中的本地和广域传输

    公开(公告)号：US07660275B2

    公开(公告)日：2010-02-09

    申请号：US10968787

    申请日：2004-10-18

    申请人： Rajiv Vijayan ,  Fuyun Ling ,  Gordon Kent Walker ,  Ramaswamy Murali ,  Ashok Mantravadi ,  Anand Subramaniam ,  Krishnamurthy Viswanathan, legal representative

    发明人： Rajiv Vijayan ,  Fuyun Ling ,  Gordon Kent Walker ,  Ramaswamy Murali ,  Ashok Mantravadi ,  Anand Subramaniam

    IPC分类号： H04H20/71

    CPC分类号： H04L5/0041 ,  H04L5/0007 ,  H04L5/0044 ,  H04L5/0048 ,  H04L12/189 ,  H04W72/005

    摘要： To broadcast different types of transmission having different tiers of coverage in a wireless broadcast network, each base station processes data for a wide-area transmission in accordance with a first mode (or coding and modulation scheme) to generate data symbols for the wide-area transmission and processes data for a local transmission in accordance with a second mode to generate data symbols for the local transmission. The first and second modes are selected based on the desired coverage for wide-area and local transmissions, respectively. The base station also generates pilots and overhead information for local and wide-area transmissions. The data, pilots, and overhead information for local and wide-area transmissions are multiplexed onto their transmission spans, which may be different sets of frequency subbands, different time segments, or different groups of subbands in different time segments. More than two different types of transmission may also be multiplexed and broadcast.

    摘要翻译： 为了在无线广播网络中广播具有不同层次的不同类型的传输，每个基站根据第一模式（或编码和调制方案）处理广域传输的数据，以产生广域的数据符号 根据第二模式传输和处理用于本地传输的数据，以产生用于本地传输的数据符号。 分别基于广域和本地传输的期望覆盖来选择第一和第二模式。 基站还为本地和广域传输生成导频和开销信息。 用于本地和广域传输的数据，导频和开销信息被复用到它们的传输跨度，其可以是不同组的频率子带，不同时间段或不同时间段中的不同子带组。 多于两种不同类型的传输也可以被复用和广播。

    MULTIPLEXING AND TRANSMISSION OF MULTIPLE DATA STREAMS IN A WIRELESS MULTI-CARRIER COMMUNICATION SYSTEM
    62.
    发明申请
    MULTIPLEXING AND TRANSMISSION OF MULTIPLE DATA STREAMS IN A WIRELESS MULTI-CARRIER COMMUNICATION SYSTEM 审中-公开
    无线多载波通信系统中多路数据流的多路复用与传输

    公开(公告)号：US20090175210A1

    公开(公告)日：2009-07-09

    申请号：US12180305

    申请日：2008-07-25

    申请人： Rajiv Vijayan ,  Aamod Khandekar ,  Fuyun Ling ,  Gordon Kent Walker ,  Ramaswamy Murali

    发明人： Rajiv Vijayan ,  Aamod Khandekar ,  Fuyun Ling ,  Gordon Kent Walker ,  Ramaswamy Murali

    IPC分类号： H04H20/71 ,  H04W72/04 ,  H04L27/28 ,  H04J11/00

    CPC分类号： H04L5/0007 ,  H04L1/0065 ,  H04L1/0083 ,  H04L5/0039 ,  H04L5/0041 ,  H04L5/0044 ,  H04L5/0048 ,  H04L5/0064 ,  H04L5/0094

    摘要： Techniques for multiplexing and transmitting multiple data streams are described. Transmission of the multiple data streams occurs in “super-frames”. Each super-frame has a predetermined time duration and is further divided into multiple (e.g., four) frames. Each data block for each data stream is outer encoded to generate a corresponding code block. Each code block is partitioned into multiple subblocks, and each data packet in each code block is inner encoded and modulated to generate modulation symbols for the packet. The multiple subblocks for each code block are transmitted in the multiple frames of the same super-frame, one subblock per frame. Each data stream is allocated a number of transmission units in each super-frame and is assigned specific transmission units to achieve efficient packing. A wireless device can select and receive individual data streams.

    摘要翻译： 描述用于复用和传输多个数据流的技术。 多个数据流的传输发生在“超帧”中。 每个超帧具有预定的持续时间并进一步分为多个（例如，四个）帧。 每个数据流的每个数据块被外部编码以生成相应的代码块。 每个码块被划分成多个子块，并且每个码块中的每个数据分组被内部编码和调制以产生分组的调制符号。 每个码块的多个子块在相同超帧的多个帧中传送，每帧一个子块。 每个数据流在每个超帧中被分配多个传输单元，并被分配特定的传输单元以实现有效的打包。 无线设备可以选择和接收各个数据流。

    Time tracking for a communication system
    65.
    发明申请
    Time tracking for a communication system 有权
    通讯系统的时间跟踪

    公开(公告)号：US20060233097A1

    公开(公告)日：2006-10-19

    申请号：US11371536

    申请日：2006-03-08

    申请人： Bojan Vrcelj ,  Ashok Mantravadi ,  Fuyun Ling ,  Rajiv Vijayan ,  Michael Wang

    发明人： Bojan Vrcelj ,  Ashok Mantravadi ,  Fuyun Ling ,  Rajiv Vijayan ,  Michael Wang

    IPC分类号： H04J11/00

    CPC分类号： H04L27/2662 ,  H04L5/0007 ,  H04L5/0048 ,  H04L25/0216 ,  H04L25/022 ,  H04L25/0228 ,  H04L27/261 ,  H04L27/265 ,  H04L27/2665 ,  H04L27/2679

    摘要： A method for characterizing a communication channel is disclosed. A detection window is moved through a channel profile to accumulate tap energies in the channel profile within the detection window into an accumulated energy curve. A peak at a maximum in the accumulated energy curve is determined. A band relative to the accumulated energy curve is defined. A first arriving path (FAP) is determined using a trailing edge found near a second end of a zone in the accumulated energy curve. A leading edge is found near a first end of the zone of the accumulated energy curve. The last arriving path (LAP) is determined using the leading edge. The band defines a zone of the accumulated energy curve at or near the maximum that is within the band.

    摘要翻译： 公开了一种用于表征通信信道的方法。 检测窗口通过通道轮廓移动，以将检测窗口内的通道轮廓中的抽头能量累积为累积的能量曲线。 确定累积能量曲线中最大值的峰值。 定义相对于累积能量曲线的带。 使用在累积能量曲线中的区域的第二端附近发现的后沿来确定第一到达路径（FAP）。 在累积能量曲线的区域的第一端附近发现前沿。 最后到达路径（LAP）使用前沿确定。 频带定义在频带内或附近的最大值处的累积能量曲线的区域。

    Efficient employment of digital upsampling using IFFT in OFDM systems for simpler analog filtering
    66.
    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。

    Trend influenced time tracking
    67.
    发明申请
    Trend influenced time tracking 有权
    趋势影响时间跟踪

    公开(公告)号：US20060215539A1

    公开(公告)日：2006-09-28

    申请号：US11371535

    申请日：2006-03-08

    申请人： Bojan Vrcelj ,  Ashok Mantravadi ,  Fuyun Ling ,  Rajiv Vijayan ,  Michael Wang

    发明人： Bojan Vrcelj ,  Ashok Mantravadi ,  Fuyun Ling ,  Rajiv Vijayan ,  Michael Wang

    IPC分类号： H04J11/00 ,  H04Q7/00 ,  H04Q7/20

    CPC分类号： H04L27/2662 ,  H04L5/0007 ,  H04L5/0048 ,  H04L25/0216 ,  H04L25/022 ,  H04L25/0228 ,  H04L27/261 ,  H04L27/265 ,  H04L27/2665 ,  H04L27/2679

    摘要： A method for determining a communication channel location is disclosed. A first subset of a plurality of channel impulse responses is averaged over a first time period to produce a first filtered channel impulse response, and a second subset of the plurality of channel impulse responses is averaged over a second time period to produce a second filtered channel impulse response. The second time period is different from the first time period, and the second subset is different from the first subset. The communication channel location is determined using the first filtered channel impulse response and the second filtered channel impulse response.

    摘要翻译： 公开了一种用于确定通信信道位置的方法。 多个信道脉冲响应的第一子集在第一时间段内被平均以产生第一经滤波的信道脉冲响应，并且在第二时间周期上平均多个信道脉冲响应的第二子集，以产生第二滤波信道 脉冲响应。 第二时间段与第一时间段不同，第二子集与第一子集不同。 使用第一滤波信道脉冲响应和第二滤波信道脉冲响应来确定通信信道位置。

    Synchronization in a broadcast OFDM system using time division multiplexed pilots
    69.
    发明申请
    Synchronization in a broadcast OFDM system using time division multiplexed pilots 审中-公开
    使用时分复用导频的广播OFDM系统中的同步

    公开(公告)号：US20050063298A1

    公开(公告)日：2005-03-24

    申请号：US10931324

    申请日：2004-08-31

    申请人： Fuyun Ling ,  Alok Gupta ,  Raghuraman Krishnamoorthi ,  Ramaswamy Murali ,  Rajiv Vijayan ,  Bojan Vrcelj

    发明人： Fuyun Ling ,  Alok Gupta ,  Raghuraman Krishnamoorthi ,  Ramaswamy Murali ,  Rajiv Vijayan ,  Bojan Vrcelj

    IPC分类号： H04B3/10 ,  H04J20060101 ,  H04J1/16 ,  H04J11/00

    CPC分类号： H04L27/2657 ,  H04L5/005 ,  H04L25/022 ,  H04L27/2613 ,  H04L27/2662 ,  H04L27/2665 ,  H04L2027/003

    摘要： In an OFDM system, a transmitter broadcasts a first TDM pilot on a first set of subbands followed by a second TDM pilot on a second set of subbands in each frame. The subbands in each set are selected from among N total subbands such that (1) an OFDM symbol for the first TDM pilot contains at least S1 identical pilot-1 sequences of length L1 and (2) an OFDM symbol for the second TDM pilot contains at least S2 identical pilot-2 sequences of length L2, where L2>L1, S1·L1=N, and S2·L2=N. The transmitter may also broadcast an FDM pilot. A receiver processes the first TDM pilot to obtain frame timing (e.g., by performing correlation between different pilot-1 sequences) and further processes the second TDM pilot to obtain symbol timing (e.g., by detecting for the start of a channel impulse response estimate derived from the second TDM pilot).

    摘要翻译： 在OFDM系统中，发射机在第一组子带上广播第一TDM导频，随后在每帧中的第二组子带上接收第二TDM导频。 每个组中的子带从N个总子带中选出，使得（1）第一TDM导频的OFDM符号包含长度为L1的至少S1个相同的导频1序列，以及（2）第二TDM导频的OFDM符号包含 至少S2个长度为L2的导频-2序列，其中L2> L1，S1.L1 = N，S2.L2 = N。 发射机还可以广播FDM导频。 接收机处理第一TDM导频以获得帧定时（例如，通过执行不同导频-1序列之间的相关）并且进一步处理第二TDM导频以获得符号定时（例如，通过检测导出的信道脉冲响应估计的开始 从第二TDM导频）。

    Coding system having state machine based interleaver
    70.
    发明授权
    Coding system having state machine based interleaver 有权
    编码系统具有基于状态机的交织器

    公开(公告)号：US06353900B1

    公开(公告)日：2002-03-05

    申请号：US09172069

    申请日：1998-10-13

    申请人： Nagabhushana T. Sindhushayana ,  Jeremy Stein ,  Rajiv Vijayan ,  Fuyun Ling

    发明人： Nagabhushana T. Sindhushayana ,  Jeremy Stein ,  Rajiv Vijayan ,  Fuyun Ling

    IPC分类号： H03M1327

    CPC分类号： H03M13/2957 ,  H03M13/2742 ,  H03M13/2757 ,  H03M13/2764 ,  H03M13/2771 ,  H03M13/2789 ,  H04L1/0043 ,  H04L1/005 ,  H04L1/0052 ,  H04L1/0066

    摘要： The present invention is a novel and improved technique for performing coding with particular application to turbo, or iterative, coding techniques. In accordance with one embodiment of the invention, interleaving is performed by generating the address of a memory using a PN state generator. Data is written into a memory in sequential order, and then read out using addresses specified by the PN state generator. To deinterleave, the interleaved data is written into a memory using addresses specified by the PN state generator, and then read out in sequential order. A set of PN state generators that provide excellent coding performance is provided.

    摘要翻译： 本发明是用于执行具有特定应用到turbo或迭代编码技术的编码的新颖和改进的技术。 根据本发明的一个实施例，通过使用PN状态发生器生成存储器的地址来执行交织。 数据按顺序写入存储器，然后使用PN状态发生器指定的地址读出。 要解交织，使用PN状态发生器指定的地址将交错数据写入存储器，然后按顺序读出。 提供了一组提供出色编码性能的PN状态发生器。