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    Systems and methods for frequency acquisition in a wireless communication network
    2.
    发明申请
    Systems and methods for frequency acquisition in a wireless communication network 审中-公开
    无线通信网络中频率采集的系统和方法

    公开(公告)号：US20050163263A1

    公开(公告)日：2005-07-28

    申请号：US11021028

    申请日：2004-12-22

    Applicant: Alok Gupta ,  Fuyun Ling

    Inventor： Alok Gupta ,  Fuyun Ling

    IPC: H04L27/06

    CPC classification number: H04L27/2665 ,  H04L7/007 ,  H04L27/2656 ,  H04L27/2657 ,  H04L27/2663 ,  H04L27/2675 ,  H04L27/2695

    Abstract: The disclosed embodiments provide for methods and systems for initial frequency acquisition in a wireless communication network. In one aspect, a method for initial frequency acquisition includes the acts of receiving a stream of input samples from a transmitter, determining an estimate for a frequency offset associated with the transmitter and the receiver based on the received input samples, and compensating for the frequency offset to achieve an initial frequency acquisition.

    Abstract translation: 所公开的实施例提供了用于无线通信网络中的初始频率采集的方法和系统。 一方面，一种用于初始频率获取的方法包括从发射机接收输入样本流的动作，基于接收到的输入样本确定与发射机和接收机相关联的频率偏移的估计，并补偿频率 偏移以实现初始频率采集。

    Automatic frequency control for a wireless communication system with multiple subcarriers
    3.
    发明申请
    Automatic frequency control for a wireless communication system with multiple subcarriers 有权
    具有多个子载波的无线通信系统的自动频率控制

    公开(公告)号：US20060215778A1

    公开(公告)日：2006-09-28

    申请号：US11372931

    申请日：2006-03-09

    Applicant: Vinay Murthy ,  Alok Gupta ,  Seong Taek Chung ,  Fuyun Ling

    Inventor： Vinay Murthy ,  Alok Gupta ,  Seong Taek Chung ,  Fuyun Ling

    IPC: H04K1/10

    CPC classification number: G06F1/0353 ,  H04L5/0007 ,  H04L5/0048 ,  H04L27/2659 ,  H04L27/266 ,  H04L27/2662 ,  H04L27/2675 ,  H04L27/2678

    Abstract: Techniques for performing frequency control in an OFDM system are described. In one aspect, frequency acquisition is performed based on a received pilot, and frequency tracking is performed based on received OFDM symbols. For frequency acquisition, an initial frequency error estimate may be derived based on the received pilot, and an automatic frequency control (AFC) loop may be initialized with the initial frequency error estimate. For frequency tracking, a frequency error estimate may be derived for each received OFDM symbol, and the AFC loop may be updated with the frequency error estimate. Frequency error in input samples is corrected by the AFC loop with the initial frequency error estimate as well as the frequency error estimate for each received OFDM symbol. In another aspect, a variable number of samples of a received OFDM symbol are selected, e.g., based on the received OFDM symbol timing, for use for frequency error estimation.

    Abstract translation: 描述在OFDM系统中执行频率控制的技术。 在一个方面，基于接收到的导频执行频率采集，并且基于接收的OFDM符号执行频率跟踪。 对于频率获取，可以基于接收到的导频来导出初始频率误差估计，并且可以利用初始频率误差估计来初始化自动频率控制（AFC）循环。 对于频率跟踪，可以针对每个接收的OFDM符号导出频率误差估计，并且可以用频率误差估计来更新AFC循环。 通过具有初始频率误差估计的AFC回路以及每个接收的OFDM符号的频率误差估计来校正输入采样中的频率误差。 在另一方面，例如基于所接收的OFDM符号定时，选择接收到的OFDM符号的可变数目的样本，以用于频率误差估计。

    Dual-loop automatic frequency control for wireless communication
    4.
    发明申请
    Dual-loop automatic frequency control for wireless communication 有权

    公开(公告)号：US20060203950A1

    公开(公告)日：2006-09-14

    申请号：US11358996

    申请日：2006-02-21

    Applicant: Seong Chung ,  Vinay Murthy ,  Alok Gupta ,  Fuyun Ling

    Inventor： Seong Chung ,  Vinay Murthy ,  Alok Gupta ,  Fuyun Ling

    IPC: H03D3/24

    CPC classification number: H03J7/04 ,  H03J1/0083

    Abstract: Techniques for performing frequency control using dual-loop automatic frequency control (AFC) are described. The dual-loop AFC includes an inner loop that corrects short-term frequency variations (e.g., due to Doppler effect) and an outer loop that corrects long-term frequency variations (e.g., due to component tolerances and temperature variations). In one design, a first inner loop is implemented for frequency control of a first system (e.g., a broadcast system), a second inner loop is implemented for frequency control of a second system (e.g., a cellular system), and at least one outer loop is implemented for adjusting a reference frequency used to receive signals from the first and second systems. Each inner loop estimates and corrects the frequency error in an input signal for the associated system and may be enabled when receiving the input signal from the system. The reference frequency may be used for frequency downconversion, sampling and/or other purposes.

    Synchronization in a broadcast OFDM system using time division multiplexed pilots
    5.
    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

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

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

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

    CPC classification number: H04L27/2657 ,  H04L5/005 ,  H04L25/022 ,  H04L27/2613 ,  H04L27/2662 ,  H04L27/2665 ,  H04L2027/003

    Abstract: 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).

    Abstract translation: 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）。

    Channel handoff methods in wireless broadcast systems
    6.
    发明授权
    Channel handoff methods in wireless broadcast systems 有权
    无线广播系统中的信道切换方法

    公开(公告)号：US09554319B2

    公开(公告)日：2017-01-24

    申请号：US11828333

    申请日：2007-07-25

    Applicant: Linbo Li ,  Ashok Mantravadi ,  Fuyun Ling ,  Raghuraman Krishnamoorthi

    Inventor： Linbo Li ,  Ashok Mantravadi ,  Fuyun Ling ,  Raghuraman Krishnamoorthi

    IPC: H04Q7/20 ,  H04W36/28 ,  H04W36/30 ,  H04W72/08

    CPC classification number: H04W36/28 ,  H04W36/30 ,  H04W72/085

    Abstract: Systems and methodologies are described that facilitate monitoring RF channels in a wireless communication environment to determine whether one or more channels comprise a forward-link-only (FLO) signal. A receiver can receive a first RF channel with a FLO signal and can monitor other RF channels for FLO signals. Upon a determination that a monitored RF channel comprises a FLO signal, the receiver can switch between the first RF channel and the monitored RF channel, employing information on current MLC decoding status, to facilitate providing seamless reception of the FLO signal, which can be superframe synchronized between RF channels. FLO signal detection can be performed using one or more of a wide-area identification channel energy detection protocol and a wide-area overhead information symbol decoding error detection protocol.

    Abstract translation: 描述了便于在无线通信环境中监视RF信道以确定一个或多个信道是包括仅前向链路（FLO）信号的系统和方法。 接收机可以接收具有FLO信号的第一RF信道，并且可以监视FLO信号的其他RF信道。 在确定被监视的RF信道包括FLO信号之后，接收机可以使用关于当前MLC解码状态的信息在第一RF信道和被监控的RF信道之间切换，以便于提供FLO信号的无缝接收，其可以是超帧 在RF信道之间同步。 可以使用广域识别信道能量检测协议和广域开销信息符号解码错误检测协议中的一个或多个来执行FLO信号检测。

    INITIALIZATION OF TIMING RECOVERY AND DECISION-FEEDBACK EQUALIZATION IN A RECEIVER
    7.
    发明申请
    INITIALIZATION OF TIMING RECOVERY AND DECISION-FEEDBACK EQUALIZATION IN A RECEIVER 审中-公开
    定时恢复的初始化和接收方的决策反馈均衡

    公开(公告)号：US20150326382A1

    公开(公告)日：2015-11-12

    申请号：US14763798

    申请日：2013-01-28

    Applicant: Jian LI ,  Yisheng XUE ,  Michael M. FAN ,  Jilei HOU ,  Yin Huang ,  Fuyun Ling ,  QUALCOMM INCORPORATED

    Inventor： Jian Li ,  Yin Huang ,  Yisheng Xue ,  Michael M. Fan ,  Fuyun Ling ,  Jilei Hou

    IPC: H04L7/00 ,  H04L25/03

    CPC classification number: H04L7/0004 ,  H04L25/03 ,  H04L25/0305 ,  H04L25/0307 ,  H04L2025/03656

    Abstract: A method of initializing a receiver is performed during an initialization mode. Timing offset values for a timing recovery circuit are repeatedly selected. For each selected timing offset value, timing recovery is performed using the timing offset value and groups of weights for a decision feedback equalizer are repeatedly selected. Each selected group of weights is used to perform blind decision feedback equalization. For each selected group of weights, a metric indicating data reception quality is computed. A timing offset value and a group of weights are chosen based on the computed metrics.

    Abstract translation: 在初始化模式期间执行初始化接收机的方法。 定时恢复电路的定时偏移值被重复选择。 对于每个选择的定时偏移值，使用定时偏移值执行定时恢复，并且重复地选择用于判决反馈均衡器的权重组。 每个选择的权重组用于执行盲判决反馈均衡。 对于每个选择的权重组，计算指示数据接收质量的度量。 基于所计算的度量来选择定时偏移值和权重组。

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