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    REDUCTION OF PEAK-TO-AVERAGE POWER RATIO IN A MOBILE TELECOMMUNICATIONS SYSTEM
    2.
    发明授权
    REDUCTION OF PEAK-TO-AVERAGE POWER RATIO IN A MOBILE TELECOMMUNICATIONS SYSTEM 有权
    异径卓越，为中档性能的关系，移动通信系统

    公开(公告)号：EP1166456B1

    公开(公告)日：2008-08-20

    申请号：EP00921281.2

    申请日：2000-04-04

    申请人： TELEFONAKTIEBOLAGET LM ERICSSON (publ)

    发明人： POPOVIC, Branislav

    IPC分类号： H04B1/707 ,  H04L27/20

    CPC分类号： H04L27/2078 ,  H04B2201/70706 ,  H04L7/04

    摘要： For one embodiment, a Random Access Channel (RACH) preamble modulation method and apparatus are disclosed in which the real (I) and imaginary (Q) components of a complex RACH preamble (b(k)) are filtered in corresponding pulse shaping filters (206, 208). Consequently, the phase transitions in the resulting signal are limited at all chip positions, and the resulting quadriphase codes produce transmitted signals with lower Peak-to-Average Power Ratios (PAPRs) than those that result using conventional Hybrid Phase-Shift Keying (HPSK) modulation schemes. On the other side, the resulting quadriphase synchronization code retains the same aperiodic autocorrelation magnitude as the original binary code (a(k)), optimized to produce the minimum probability of incorrect synchronization.

    Search window delay tracking in code division multiple access communication systems
    3.
    发明授权
    Search window delay tracking in code division multiple access communication systems 有权
    码分多址通信系统中的搜索窗延迟跟踪

    公开(公告)号：EP1082820B1

    公开(公告)日：2006-08-23

    申请号：EP99948574.1

    申请日：1999-04-29

    申请人： TELEFONAKTIEBOLAGET LM ERICSSON (publ)

    发明人： POPOVIC, Branislav ,  FRANK, Georg ,  SCHULIST, Matthias ,  KLANG, Göran

    IPC分类号： H04B1/707

    CPC分类号： H04B1/7085 ,  G01S5/0215 ,  H04B1/7113 ,  H04B1/7117

    摘要： The present invention provides a search window delay tracking procedure for use in a multipath search processor of a CDMA radio receiver. A channel impulse response is estimated for a received signal containing plural paths, each path having a corresponding path delay. A search window defines a delay profile that contains the plural paths of the received signal. A mean or average delay is calculated for the estimated channel impulse response (CIR), and an error is determined between the mean CIR delay and a desired delay position corresponding to the center of the CIR search window. An adjustment is made to reduce that error so that the center of the search window and the mean CIR delay are aligned. The error may be processed either linearly (in one embodiment) or non-linearly (in another embodiment) to minimize the error and to reduce an influence of noise. A non-linear filtering process includes calculating a delay spread from the mean CIR delay calculated for successive processing cycles of a window delay tracking procedure corresponding to each new input. A difference is determined between the successive delay spreads. Adjustment signal is set equal to the error signal if the difference is less than or equal to a threshold. Alternatively, the adjustment signal is set to zero if the difference is greater than the threshold. Consequently, if the delay spread in the current iteration is significantly different from the delay spread in the previous iteration, the new error sample calculated in the current iteration is considered unreliable, and no adjustment is made.

    摘要翻译： 本发明提供了用于CDMA无线电接收机的多路径搜索处理器中的搜索窗口延迟跟踪过程。 为包含多个路径的接收信号估计信道脉冲响应，每个路径具有对应的路径延迟。 搜索窗口定义了包含接收信号的多个路径的延迟分布。 计算估计的信道脉冲响应（CIR）的平均或平均延迟，并且在平均CIR延迟和对应于CIR搜索窗口的中心的期望延迟位置之间确定误差。 进行调整以减少该错误，使得搜索窗口的中心和平均CIR延迟对齐。 可以线性地（在一个实施例中）或非线性地（在另一个实施例中）处理该误差以最小化误差并且减少噪声的影响。 非线性滤波处理包括根据对应于每个新输入的窗延迟追踪过程的连续处理循环计算的平均CIR延迟来计算延迟扩展。 在连续的延迟差值之间确定差值。 如果差值小于或等于阈值，则将调整信号设置为等于误差信号。 或者，如果差值大于阈值，则调整信号被设置为零。 因此，如果当前迭代中的延迟扩展与先前迭代中的延迟扩展明显不同，则在当前迭代中计算的新的误差样本被认为是不可靠的，并且不进行调整。

    REDUCTION OF PEAK-TO-AVERAGE POWER RATIO IN A MOBILE TELECOMMUNICATIONS SYSTEM
    4.
    发明公开
    REDUCTION OF PEAK-TO-AVERAGE POWER RATIO IN A MOBILE TELECOMMUNICATIONS SYSTEM 有权
    异径卓越，为中档性能的关系，移动通信系统

    公开(公告)号：EP1166456A1

    公开(公告)日：2002-01-02

    申请号：EP00921281.2

    申请日：2000-04-04

    申请人： TELEFONAKTIEBOLAGET LM ERICSSON (publ)

    发明人： POPOVIC, Branislav

    IPC分类号： H04B1/707 ,  H04L27/20

    CPC分类号： H04L27/2078 ,  H04B2201/70706 ,  H04L7/04

    摘要： For one embodiment, a Random Access Channel (RACH) preamble modulation method and apparatus are disclosed in which the real (I) and imaginary (Q) components of a complex RACH preamble (b(k)) are filtered in corresponding pulse shaping filters (206, 208). Consequently, the phase transitions in the resulting signal are limited at all chip positions, and the resulting quadriphase codes produce transmitted signals with lower Peak-to-Average Power Ratios (PAPRs) than those that result using conventional Hybrid Phase-Shift Keying (HPSK) modulation schemes. On the other side, the resulting quadriphase synchronization code retains the same aperiodic autocorrelation magnitude as the original binary code (a(k)), optimized to produce the minimum probability of incorrect synchronization.