利索-全球专利检索

  1. 登录
  2. 注册

搜索结果

20 条记录 (耗时 0.016 秒)

    Decision feedback equalizer with dynamic feedback control
    1.
    发明授权
    Decision feedback equalizer with dynamic feedback control 有权
    具有动态反馈控制的决策反馈均衡器

    公开(公告)号：US07394849B2

    公开(公告)日：2008-07-01

    申请号：US11539810

    申请日：2006-10-09

    申请人： Edem Ibragimov ,  Qian Yu ,  Prashant Choudhary

    发明人： Edem Ibragimov ,  Qian Yu ,  Prashant Choudhary

    IPC分类号： H03H7/30 ,  H03H7/40 ,  H03K5/159

    CPC分类号： H04L25/03057 ,  H03H21/0012 ,  H03H2021/0096 ,  H04L25/03063 ,  H04L25/0307 ,  H04L2025/0349 ,  H04L2025/03509 ,  H04L2025/03611

    摘要： A decision feedback equalizer with dynamic feedback control for use in an adaptive signal equalizer. Timing within the decision feedback loop is dynamically controlled to optimize recovery of the data signal by the output signal slicer. The dynamic timing is controlled by a signal formed as a combination of feedback and feedforward signals. The feedback signal is an error signal related to a difference between pre-slicer and post-slicer signals. The feedforward signal is formed by differentiating and delaying the incoming data signal.

    摘要翻译： 具有用于自适应信号均衡器的动态反馈控制的判决反馈均衡器。 动态控制决策反馈环路内的定时，以优化输出信号限幅器对数据信号的恢复。 动态定时由形成为反馈和前馈信号的组合的信号控制。 反馈信号是与预切片器和后切片器信号之间的差异相关的误差信号。 前馈信号通过差分和延迟输入数据信号来形成。

    METHOD AND APPARATUS TO OPTIMIZE ADAPTIVE RADIO-FREQUENCY SYSTEMS
    2.
    发明申请
    METHOD AND APPARATUS TO OPTIMIZE ADAPTIVE RADIO-FREQUENCY SYSTEMS 有权
    优化自适应无线电频率系统的方法和装置

    公开(公告)号：US20110258591A1

    公开(公告)日：2011-10-20

    申请号：US12762098

    申请日：2010-04-16

    申请人： Arvind V. Keerthi ,  Prashant Choudhary

    发明人： Arvind V. Keerthi ,  Prashant Choudhary

    IPC分类号： G06F17/50

    CPC分类号： G06F17/5063 ,  G06F2217/08 ,  G06F2217/78

    摘要： A performance optimizing circuit is provided for a signal processing system which is parameterized by a set of coefficients that vary the operational characteristics of the signal processing system. The performance optimizing circuit receives as input a reference signal and an output signal of the signal processing system. The performance optimizing circuit may include (a) a cost computation circuit that receives the reference signal and the output signal and provides as output a cost signal representing a cost function computed using a set of current values for the set of coefficients, the output signal and the reference signal; and (b) a cost optimizer circuit that, at each of a plurality of successive time intervals, evaluates one or more values of the cost signal in the cost computation circuit and provides to the signal processing system a new set of values for the set of coefficients. The cost optimizer circuit implements two or more of the random search, parabolic interpolation and hill climbing techniques.

    摘要翻译： 为信号处理系统提供性能优化电路，该信号处理系统由改变信号处理系统的操作特性的一组系数参数化。 性能优化电路接收信号处理系统的参考信号和输出信号作为输入。 性能优化电路可以包括（a）成本计算电路，其接收参考信号和输出信号，并提供代表使用一组系数的当前值所计算的成本函数的成本信号作为输出，输出信号和 参考信号; 以及（b）成本优化器电路，其在多个连续时间间隔中的每一个处评估所述成本计算电路中的所述成本信号的一个或多个值，并向所述信号处理系统提供所述一组 系数。 成本优化器电路实现了随机搜索，抛物线插值和爬山技术中的两种或多种。

    Method and apparatus for discrete multitone communication bit allocation
    5.
    发明授权
    Method and apparatus for discrete multitone communication bit allocation 有权
    用于离散多音通信位分配的方法和装置

    公开(公告)号：US06516027B1

    公开(公告)日：2003-02-04

    申请号：US09252418

    申请日：1999-02-18

    申请人： Samir Kapoor ,  Prashant Choudhary

    发明人： Samir Kapoor ,  Prashant Choudhary

    IPC分类号： H04B346

    CPC分类号： H04L5/006 ,  H04L5/0007 ,  H04L5/0046 ,  H04L5/1438

    摘要： A method and apparatus for allocating bits to subchannels in a discrete multitone environment. The method employs the use of precalculated and prestored look-up tables which take into account a desired bit error rate, signal-to-noise ratio gap for a particular coding scheme, and gain scaling factor. This eliminates the need for the communication device to conduct complex and time consuming calculations. During the training sequence portion of data communication channel establishment, the measured signal-to-noise ratio for each subchannel is compared with values in the precalculated look-up tables to determine the bit allocation for that subchannel. The bit allocation value is stored in a data structure in the communication device. A gain scaling factor for each subchannel is then determined and stored as a data structure. The bit allocation and gain scaling data can then be transmitted to a partner communication device in order to instruct the transmitter how to load each subchannel.

    摘要翻译： 一种用于在离散多媒体环境中分配比特到子信道的方法和装置。 该方法采用预先计算和预存的查找表，其考虑了特定编码方案的期望误码率，信噪比间隙以及增益缩放因子。 这消除了对通信设备进行复杂和耗时的计算的需要。 在数据通信信道建立的训练序列部分期间，将每个子信道的测量信噪比与预先计算的查找表中的值进行比较，以确定该子信道的比特分配。 位分配值存储在通信设备中的数据结构中。 然后确定每个子信道的增益比例因子并将其存储为数据结构。 然后可以将比特分配和增益缩放数据发送​​到伙伴通信设备，以便指示发射机如何加载每个子信道。

    DECISION FEEDBACK EQUALIZER WITH DYNAMIC FEEDBACK CONTROL
    7.
    发明申请
    DECISION FEEDBACK EQUALIZER WITH DYNAMIC FEEDBACK CONTROL 有权
    具有动态反馈控制的决策反馈均衡器

    公开(公告)号：US20070091995A1

    公开(公告)日：2007-04-26

    申请号：US11539810

    申请日：2006-10-09

    申请人： Edem Ibragimov ,  Qian Yu ,  Prashant Choudhary

    发明人： Edem Ibragimov ,  Qian Yu ,  Prashant Choudhary

    IPC分类号： H03H7/30 ,  H04B1/10

    CPC分类号： H04L25/03057 ,  H03H21/0012 ,  H03H2021/0096 ,  H04L25/03063 ,  H04L25/0307 ,  H04L2025/0349 ,  H04L2025/03509 ,  H04L2025/03611

    摘要： A decision feedback equalizer with dynamic feedback control for use in an adaptive signal equalizer. Timing within the decision feedback loop is dynamically controlled to optimize recovery of the data signal by the output signal slicer. The dynamic timing is controlled by a signal formed as a combination of feedback and feedforward signals. The feedback signal is an error signal related to a difference between pre-slicer and post-slicer signals. The feedforward signal is formed by differentiating and delaying the incoming data signal.

    摘要翻译： 具有用于自适应信号均衡器的动态反馈控制的判决反馈均衡器。 动态控制决策反馈环路内的定时，以优化输出信号限幅器对数据信号的恢复。 动态定时由形成为反馈和前馈信号的组合的信号控制。 反馈信号是与预切片器和后切片器信号之间的差异相关的误差信号。 前馈信号通过差分和延迟输入数据信号来形成。

    Linear minimum mean square error equalization with interference cancellation for mobile communication forward links utilizing orthogonal codes covered by long pseudorandom spreading codes
    8.
    发明授权
    Linear minimum mean square error equalization with interference cancellation for mobile communication forward links utilizing orthogonal codes covered by long pseudorandom spreading codes 失效
    使用由长伪距扩展码覆盖的正交码的移动通信正向链路的线性最小均方误差均衡与干扰消除

    公开(公告)号：US06956893B2

    公开(公告)日：2005-10-18

    申请号：US09933365

    申请日：2001-08-20

    申请人： Colin D. Frank ,  Eugene Visotsky ,  Prashant Choudhary ,  Amitava Ghosh

    发明人： Colin D. Frank ,  Eugene Visotsky ,  Prashant Choudhary ,  Amitava Ghosh

    IPC分类号： H04B1/7105 ,  H04B1/7107 ,  H04L25/03 ,  H04K1/00

    CPC分类号： H04B1/71055 ,  H04B1/71075 ,  H04L2025/03375 ,  H04L2025/03477 ,  H04L2025/03605

    摘要： The present invention provides linear MMSE equalization with parallel interference cancellation for symbol determination in a forward link of a CDMA communication system which has a plurality of code channels in use. Use of the linear MMSE equalization with parallel interference cancellation of the present invention provides significantly increased performance. The preferred method linearly filters a received signal to form a first filtered signal (410), despreads and demodulates the first filtered signal (415, 420) and provides a plurality of symbol estimates for all corresponding code channels (430). An estimated transmitted signal is generated from the plurality of symbol estimates (435), and with a channel estimate (405), an estimated received signal is generated (440). A residual signal is determined as a difference between the received signal and the estimated received signal, is linearly filtered (445), and then combined with the estimated transmitted signal to form a next, enhanced estimated transmitted signal (450). This next estimated transmitted signal is despread (455, 460) and utilized to provide a next plurality of symbol estimates, for a selected code channel of the plurality of channels, for subsequent use in error correction and decoding, and further use by a subscriber (465, 475).

    摘要翻译： 本发明提供了具有并行干扰消除的线性MMSE均衡，用于在使用多个代码信道的CDMA通信系统的前向链路中进行符号确定。 使用本发明的具有并行干扰消除的线性MMSE均衡提供了显着提高的性能。 优选的方法是对接收到的信号进行线性滤波以形成第一滤波信号（410），对第一滤波信号（415,420）进行解扩和解调，并为所有对应的码信道提供多个符号估计（430）。 从多个符号估计（435）生成估计的发送信号，并且利用信道估计（405）生成估计的接收信号（440）。 确定残差信号作为接收信号与估计的接收信号之间的差值，被线性滤波（445），然后与所估计的发射信号组合以形成下一增强估计发射信号（450）。 该下一个估计的传输信号被解扩展（455,460），并且用于为多个信道的所选择的码信道提供下一个多个符号估计，用于随后在纠错和解码中使用，并由用户进一步使用 465,475）。