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    Method and apparatus for performing frequency tracking based on diversity transmitted pilots in a CDMA communication system
    3.
    发明授权
    Method and apparatus for performing frequency tracking based on diversity transmitted pilots in a CDMA communication system 有权
    一种用于在CDMA通信系统中基于分集传输导频执行频率跟踪的方法和装置

    公开(公告)号：US07430191B2

    公开(公告)日：2008-09-30

    申请号：US09950744

    申请日：2001-09-10

    Applicant: Parvathanathan Subrahmanya ,  Andrew Sendonaris

    Inventor： Parvathanathan Subrahmanya ,  Andrew Sendonaris

    IPC: H04B7/216

    CPC classification number: H04L27/2332 ,  H04B2201/70701 ,  H04L2027/0055 ,  H04L2027/0065 ,  H04L2027/0081 ,  H04L2027/0087

    Abstract: Techniques to acquire and track a received signal instance (or multipath) based on one or more transmitted pilots. In an aspect, a frequency tracking loop is provided to acquire and track the multipath, and supports a number of loop modes (e.g., acquisition and tracking modes). Each loop mode may be associated with a respective frequency detector and a set of values for a set of elements in the loop. In another aspect, several frequency detectors are provided for deriving estimates of the frequency error in the downconversion of the multipath (e.g., from radio frequency to baseband). In one design, maximum likelihood estimates of the frequency error are derived based on the recovered pilot symbols. In another design, the frequency error estimates for the multipath are derived based on the frequency error estimated for each transmitted signal.

    Abstract translation: 基于一个或多个发射的导频获取和跟踪接收到的信号实例（或多路径）的技术。 在一方面，提供频率跟踪环以获取和跟踪多路径，并且支持多种环路模式（例如，采集和跟踪模式）。 每个循环模式可以与相应的频率检测器和一组循环中的元件的值相关联。 在另一方面，提供了几个频率检测器用于导出多路径下变频（例如，从射频到基带）中的频率误差的估计。 在一种设计中，基于恢复的导频符号导出频率误差的最大似然估计。 在另一种设计中，基于针对每个发射信号估计的频率误差导出多路径的频率误差估计。

    Reliability determination and combining of power control commands received in a wireless communication system
    8.
    发明授权
    Reliability determination and combining of power control commands received in a wireless communication system 有权
    在无线通信系统中接收的功率控制命令的可靠性确定和组合

    公开(公告)号：US07340268B2

    公开(公告)日：2008-03-04

    申请号：US10457846

    申请日：2003-06-10

    Applicant: Hyukjun Oh ,  Parvathanathan Subrahmanya ,  Nitin Kasturi ,  Messay Amerga ,  Chih-Ping Hsu ,  Christopher C. Riddle ,  Andrew Sendonaris

    Inventor： Hyukjun Oh ,  Parvathanathan Subrahmanya ,  Nitin Kasturi ,  Messay Amerga ,  Chih-Ping Hsu ,  Christopher C. Riddle ,  Andrew Sendonaris

    IPC: H04B7/00 ,  H04Q7/20

    CPC classification number: H04W52/56 ,  H04W52/40 ,  H04W52/58

    Abstract: The reliability of transmit power control (TPC) commands received from a transmitter is determined based on a TPC target value. The TPC target value is derived based on a TPC threshold and possibly a weight, depending on the receiver implementation. A received TPC command is considered reliable if its absolute value exceeds the TPC target value. Received TPC commands deemed as unreliable are discarded and not used for power control. Multiple TPC target values, used for detecting UP and DOWN commands, may be derived with multiple scaling factors. For a receiver in soft handover and receiving TPC commands from multiple transmitters, a different TPC target value may be derived for each transmitter. The received TPC commands for each transmitter are compared against that transmitter's TPC target value. Received TPC commands deemed as unreliable are discarded and not combined.

    Abstract translation: 基于TPC目标值确定从发射机接收的发射功率控制（TPC）命令的可靠性。 TPC目标值基于TPC阈值和可能的权重导出，这取决于接收机实现。 如果接收到的TPC命令的绝对值超过TPC目标值，则认为它是可靠的。 被认为不可靠的TPC命令被丢弃，不用于功率控制。 用于检测UP和DOWN命令的多个TPC目标值可以用多个缩放因子导出。 对于软切换中的接收机和从多个发射机接收TPC命令，可以为每个发射机导出不同的TPC目标值。 每个发射机接收的TPC命令与该发射机的TPC目标值进行比较。 被认为不可靠的TPC命令被丢弃并不组合。

    Method and apparatus for filtering noisy estimates to reduce estimation errors
    10.
    发明授权
    Method and apparatus for filtering noisy estimates to reduce estimation errors 有权
    用于过滤噪声估计以减少估计误差的方法和装置

    公开(公告)号：US08406359B2

    公开(公告)日：2013-03-26

    申请号：US12712907

    申请日：2010-02-25

    Applicant: Gokhan Mergen ,  Parvathanathan Subrahmanya ,  Vijayaraj Alilaghatta-Kantharaj ,  Nitin Kasturi

    Inventor： Gokhan Mergen ,  Parvathanathan Subrahmanya ,  Vijayaraj Alilaghatta-Kantharaj ,  Nitin Kasturi

    IPC: H04B1/10

    CPC classification number: H04L25/025 ,  H04B17/3913 ,  H04B2201/70701 ,  H04L25/0212 ,  H04L25/0228 ,  H04L25/03038

    Abstract: Techniques for filtering noisy estimates to reduce estimation errors are described. A sequence of input values (e.g., for an initial channel impulse response estimate (CIRE)) is filtered with an infinite impulse response (IIR) filter having at least one coefficient to obtain a sequence of output values (e.g., for a filtered CIRE). The coefficient(s) are updated based on the sequence of input values with an adaptive filter, a bank of prediction filters, or a normalized variation technique. To update the coefficient(s) with the adaptive filter, a sequence of predicted values is derived based on the sequence of input values. Prediction errors between the sequence of predicted values and the sequence of input values are determined and filtered to obtain filtered prediction errors. The coefficient(s) of the IIR filter are then updated based on the prediction errors and the filtered prediction errors.

    Abstract translation: 描述了用于过滤噪声估计以减少估计误差的技术。 输入值的序列（例如，对于初始信道脉冲响应估计（CIRE））用具有至少一个系数的无限脉冲响应（IIR）滤波器进行滤波以获得输出值序列（例如，对于滤波后的CIRE） 。 基于具有自适应滤波器，预测滤波器组或归一化变化技术的输入值的序列来更新系数。 为了用自适应滤波器更新系数，基于输入值的序列导出预测值序列。 确定并过滤预测值序列与输入值序列之间的预测误差，以获得滤波预测误差。 然后基于预测误差和滤波预测误差来更新IIR滤波器的系数。

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