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    Frequency domain filtering to improve channel estimation in multicarrier systems
    2.
    发明授权
    Frequency domain filtering to improve channel estimation in multicarrier systems 失效
    频域滤波以改善多载波系统中的信道估计

    公开(公告)号：US07616711B2

    公开(公告)日：2009-11-10

    申请号：US11022360

    申请日：2004-12-22

    申请人： Dhananjay Ashok Gore ,  Avneesh Agrawal ,  Aamod Khandekar ,  Alexei Gorokhov

    发明人： Dhananjay Ashok Gore ,  Avneesh Agrawal ,  Aamod Khandekar ,  Alexei Gorokhov

    IPC分类号： H03D1/00 ,  H04L27/06

    CPC分类号： H04L27/2647 ,  H04L5/0007 ,  H04L5/0048 ,  H04L5/006 ,  H04L25/022 ,  H04L25/0226 ,  H04L25/023

    摘要： A channel estimation system comprises a filtering component that selectively scales a plurality of carriers as a function of location of the plurality of carriers within a frequency band, wherein the plurality of carriers comprises at least one data carrier and at least one pilot carrier. A component thereafter extrapolates an observation from the at least one pilot carrier, wherein a channel is estimated as a function of the extrapolated observation. The scaling of the carriers facilitates reducing a flooring effect associated with channel estimation. The filtering component can be employed at a transmitter and/or at a receiver, and can be activated and/or deactivated as a function of a sensed data packet type.

    摘要翻译： 信道估计系统包括：滤波部件，其选择性地按照频带内的多个载波的位置来缩放多个载波，其中所述多个载波包括至少一个数据载波和至少一个导频载波。 然后，组件从至少一个导频载波外推观测，其中，估计信道作为外推观测的函数。 载波的缩放有助于减少与信道估计相关的地板效应。 滤波组件可以在发射机和/或接收机处采用，并且可以作为感测数据分组类型的功能被激活和/或去激活。

    Unified pulse shaping for multi-carrier and single-carrier waveforms
    3.
    发明授权
    Unified pulse shaping for multi-carrier and single-carrier waveforms 有权
    统一的脉冲整形用于多载波和单载波波形

    公开(公告)号：US08484272B2

    公开(公告)日：2013-07-09

    申请号：US11022537

    申请日：2004-12-22

    申请人： Dhananjay Ashok Gore ,  Avneesh Agrawal ,  Aamod Khandekar

    发明人： Dhananjay Ashok Gore ,  Avneesh Agrawal ,  Aamod Khandekar

    IPC分类号： G06F17/14

    CPC分类号： H04L5/0048 ,  H04L5/0007 ,  H04L5/0044 ,  H04L25/03834 ,  H04L27/0008 ,  H04L27/2607 ,  H04L27/2626 ,  H04L27/2647

    摘要： To transmit a multi-carrier signal, a transmitter provides zero symbols for guard subbands, performs OFDM modulation, and filters the resultant time-domain samples with a pulse shaping filter. To transmit a single-carrier signal, the transmitter partitions the single-carrier signal into segments. Each segment contains up to K samples and is padded, if needed, to the length of an OFDM symbol. Each padded segment is transformed from the time domain to the frequency domain to generate a corresponding frequency-domain segment with K symbols. For each frequency-domain segment, the symbols corresponding to the guard subbands are set to zero. Each frequency-domain segment is then transformed from the frequency domain to the time domain to generate a corresponding time-domain segment. A cyclic prefix may or may not be appended to each time-domain segment. Each time-domain segment is filtered with the same pulse shaping filter to generate an output waveform for the single-carrier signal.

    摘要翻译： 为了发送多载波信号，发射机为保护子带提供零符号，执行OFDM调制，并用脉冲整形滤波器对合成的时域采样进行滤波。 为了发送单载波信号，发射机将单载波信号分割成段。 每个段包含多达K个样本，并且如果需要，则填充到OFDM符号的长度。 每个填充段从时域变换到频域，以产生具有K个符号的对应的频域段。 对于每个频域段，对应于保护子带的符号被设置为零。 然后将每个频域段从频域变换到时域以产生对应的时域段。 循环前缀可以附加到每个时域段，也可以不附加到每个时域段。 每个时域分段用相同的脉冲整形滤波器滤波，以产生单载波信号的输出波形。

    Incremental pilot insertion for channnel and interference estimation
    4.
    发明授权
    Incremental pilot insertion for channnel and interference estimation 有权
    增量导频插入用于信道和干扰估计

    公开(公告)号：US08085875B2

    公开(公告)日：2011-12-27

    申请号：US11128976

    申请日：2005-05-13

    申请人： Dhananjay Ashok Gore ,  Avneesh Agrawal ,  Aamod Khandekar

    发明人： Dhananjay Ashok Gore ,  Avneesh Agrawal ,  Aamod Khandekar

    IPC分类号： H04L27/00

    CPC分类号： H04L25/0226 ,  H04L5/0007 ,  H04L5/005 ,  H04L5/0051 ,  H04L5/006

    摘要： Dynamic resource allocation systems, apparatus, and methods are disclosed for selectively improving the ability of a receiver to determine a channel estimate in an Orthogonal Frequency Division Multiple Access (OFDMA) system. A wireless communication system can use a common pilot channel configuration to aid channel estimation in one or more receivers in communication with the system. A receiver in communication with the system may be unable to demodulate received data due to an inaccurate channel estimate. The receiver can communicate to a transmitter in the system a request for additional channel estimation resources. The wireless communication system can provide additional channel estimation resources by inserting dedicated pilot channels into one or more of the frequencies allocated to symbols for the receiver. If the receiver is still unable to demodulate received data, the wireless communication system can incrementally insert additional pilot channels in the symbol associated with the receiver.

    摘要翻译： 公开了动态资源分配系统，装置和方法，用于选择性地提高接收机在正交频分多址（OFDMA）系统中确定信道估计的能力。 无线通信系统可以使用公共导频信道配置来辅助与系统通信的一个或多个接收机中的信道估计。 与系统通信的接收机可能由于不准确的信道估计而无法解调所接收的数据。 接收机可以向系统中的发射机通信另外的信道估计资源的请求。 无线通信系统可以通过将专用导频信道插入分配给接收机的符号的一个或多个频率来提供额外的信道估计资源。 如果接收机仍然不能解调所接收的数据，则无线通信系统可以递增地在与接收机相关联的符号中插入附加的导频信道。

    METHOD AND APPARATUS FOR ANTENNA DIVERSITY IN MULTI-INPUT MULTI-OUTPUT COMMUNICATION SYSTEMS
    6.
    发明申请
    METHOD AND APPARATUS FOR ANTENNA DIVERSITY IN MULTI-INPUT MULTI-OUTPUT COMMUNICATION SYSTEMS 有权
    多输入多输出通信系统中天线多样性的方法与装置

    公开(公告)号：US20120120925A1

    公开(公告)日：2012-05-17

    申请号：US13271121

    申请日：2011-10-11

    申请人： Tamer Kadous ,  Aamod Khandekar ,  Dhananjay Ashok Gore ,  Alexei Gorokhov

    发明人： Tamer Kadous ,  Aamod Khandekar ,  Dhananjay Ashok Gore ,  Alexei Gorokhov

    IPC分类号： H04W72/04

    CPC分类号： H04L5/0023 ,  H04B7/0456 ,  H04B7/061 ,  H04B7/0671 ,  H04B7/0691 ,  H04B7/0697 ,  H04L27/2602

    摘要： Transmission schemes that can flexibly achieve the desired spatial multiplexing order, spatial diversity order, and channel estimation overhead order are described. For data transmission, the assigned subcarriers and spatial multiplexing order (M) for a receiver are determined, where M≧1. For each assigned subcarrier, M virtual antennas are selected from among V virtual antennas formed with V columns of an orthonormal matrix, where V≧M. V may be selected to achieve the desired spatial diversity order and channel estimation overhead order. Output symbols are mapped to the M virtual antennas selected for each assigned subcarrier by applying the orthonormal matrix. Pilot symbols are also mapped to the V virtual antennas. The mapped symbols are provided for transmission from T transmit antennas, where T≧V. Transmission symbols are generated for the mapped symbols, e.g, based on OFDM or SC-FDMA. Different cyclic delays may be applied for the T transmit antennas to improve diversity.

    摘要翻译： 描述了可以灵活地实现期望的空间复用顺序，空间分集顺序和信道估计开销顺序的传输方案。 对于数据传输，确定接收机的分配子载波和空间复用顺序（M），其中M≥1。 对于每个分配的子载波，从由正交矩阵的V列形成的V个虚拟天线中选择M个虚拟天线，其中V≥M。 可以选择V以实现期望的空间分集顺序和信道估计开销顺序。 通过应用正交矩阵将输出符号映射到为每个分配的副载波选择的M个虚拟天线。 导频符号也映射到V虚拟天线。 映射的符号被提供用于从T发射天线发射，其中T≥V。 为映射符号生成传输符号，例如基于OFDM或SC-FDMA。 可以对T发射天线应用不同的循环延迟以改善分集。

    METHOD OF PROVIDING A GAP INDICATION DURING A STICKY ASSIGNMENT
    9.
    发明申请
    METHOD OF PROVIDING A GAP INDICATION DURING A STICKY ASSIGNMENT 有权
    在贴纸分配过程中提供差距指示的方法

    公开(公告)号：US20110282999A1

    公开(公告)日：2011-11-17

    申请号：US13190421

    申请日：2011-07-25

    申请人： Edward Harrison Teague ,  Aamod Khandekar ,  Dhananjay Ashok Gore

    发明人： Edward Harrison Teague ,  Aamod Khandekar ,  Dhananjay Ashok Gore

    IPC分类号： G06F15/173

    CPC分类号： H04L5/0037 ,  H04W28/04 ,  H04W72/04 ,  H04W76/25

    摘要： A method and apparatus are provided to manage the assignment transmission resource of forward and reserve link that is assigned to transmitting entity for a period of time. An indication of a gap is provided whenever the transmitting entity is not transmitting actual data packets (e.g. whole or part of intended data or content), yet the transmitting entity is to maintain the assignment of the allocated resource. For example, an erasure signature packet comprising a first data pattern is transmitted on the assigned resource when there is no actual data to transmit on the assigned resource.

    摘要翻译： 提供了一种方法和装置，用于管理分配给发送实体一段时间的前向和后退链路的分配传输资源。 只要发送实体不发送实际数据分组（例如，预期数据或内容的全部或部分），并且发送实体将维护分配的资源的分配，则提供间隙的指示。 例如，当在分配的资源上没有要发送的实际数据时，在分配的资源上发送包括第一数据模式的擦除签名分组。

    Shared signaling channel
    10.
    发明授权
    Shared signaling channel 有权
    共享信令通道

    公开(公告)号：US09225488B2

    公开(公告)日：2015-12-29

    申请号：US11261158

    申请日：2005-10-27

    申请人： Aamod Khandekar ,  Alexei Gorokhov ,  Dhananjay Ashok Gore ,  Edward Harrison Teague ,  Min Dong

    发明人： Aamod Khandekar ,  Alexei Gorokhov ,  Dhananjay Ashok Gore ,  Edward Harrison Teague ,  Min Dong

    IPC分类号： H04J1/00 ,  H04L5/00

    CPC分类号： H04L5/0044 ,  H04L5/0007 ,  H04L5/0048 ,  H04L5/0053

    摘要： A shared signaling channel can be used in an Orthogonal Frequency Division Multiple Access (OFDMA) communication system to provide signaling, acknowledgement, and power control messages to access terminals within the system. The shared signaling channel can be assigned to a predetermined number of sub-carriers within any frame. The assignment of a predetermined number of sub-carriers to the shared signaling channel establishes a fixed bandwidth overhead for the channel. The actual sub-carriers assigned to the channel can be varied periodically, and can vary according to a predetermined frequency hopping schedule. The amount of signal power allocated to the signaling channel can vary on a per symbol basis depending on the power requirements of the communication link. The shared signaling channel can direct each message carried on the channel to one or more access terminals. Unicast messages allow the channel power to be controlled per the needs of individual communication links.

    摘要翻译： 可以在正交频分多址（OFDMA）通信系统中使用共享信令信道，以向系统内的接入终端提供信令，确认和功率控制消息。 共享信令信道可以被分配给任何帧内的预定数量的子载波。 将预定数量的子载波分配给共享信令信道为信道建立固定的带宽开销。 分配给信道的实际子载波可以周期性地变化，并且可以根据预定的跳频调度而变化。 分配给信令信道的信号功率的量可以根据通信链路的功率要求在每个符号的基础上变化。 共享信令信道可以将信道上承载的每个消息引导到一个或多个接入终端。 单播消息允许根据各个通信链路的需要来控制信道功率。