公开(公告)号：US20060230089A1

公开(公告)日：2006-10-12

申请号：US10546696

申请日：2004-02-24

申请人： Ian Scott ,  Refik Shadich ,  William Siddall

发明人： Ian Scott ,  Refik Shadich ,  William Siddall

IPC分类号： G06F1/02

CPC分类号： H04L27/156 ,  H04L27/233

摘要： The present invention relates to a method and hardware for estimating the frequency offset of a signal. The method includes obtaining samples of the signal at at least two instants in time, and utilising the samples in a mathematical equation relating estimated offset frequency to the samples, wherein the mathematical equation is derived based on the premise of a modulating signal with a complex frequency.

摘要翻译： 本发明涉及用于估计信号频偏的方法和硬件。 该方法包括在至少两个时刻获得该信号的样本，并且利用与估计的偏移频率相关的数学方程中的样本与样本，其中该数学方程式是基于具有复频率的调制信号的前提 。

公开(公告)号：US20030181183A1

公开(公告)日：2003-09-25

申请号：US10368634

申请日：2003-02-20

发明人： Alessandro Ventura

IPC分类号： H04B001/06

CPC分类号： H04L27/233 ,  H04L27/0014 ,  H04L2027/0028 ,  H04L2027/0057 ,  H04L2027/0095

摘要： Some improvements to the conventional algorithms for data aided frequency synchronisation in cellular systems are introduced in a new method executable by the user equipments of various standards, i.e. 3GPP CDMA-TDMA, FDD mode at 3.84 Mcps, TDD mode at 3.84 Mcps, TDD mode at 1.28 Mcps; CWTS TD-SCDMA; GSM/DCS/GPRS. The method begins to obtain the suboptimal frequency errors null{tilde over (f)}i using a well known formula which calculates the argument of the autocorrelation over a subset of the baseband samples of the detected training sequence. The errors null{tilde over (f)}i are stored into a shift register L-position long and averaged to obtain an estimated frequency error null{circumflex over (f)}i used for recursively correcting the reference frequency of the local oscillator, as: {circumflex over (f)}inull{circumflex over (f)}inull1nullKnull{circumflex over (f)}i where K (0nullKnull1) is a weighting factor. Contrarily to the simple averaged error of the prior art, a sign criterion is used by which the average is performed on the only terms having the most recurrent algebraic sign among the stored terms null{tilde over (f)}i. The content of the shift register is corrected after each non-null frequency correction by subtracting Knullnull{circumflex over (f)}i to all the stored terms null{tilde over (f)}i. Besides the frequency is corrected upon the following optional conditions, each other independents: The number of terms null{tilde over (f)}i having equal algebraic sign is greater than a constant null lower than L. The standard deviation null of the averaged terms null{tilde over (f)}i is lower than nullnullnullold, being nullold the null of the last non-null frequency correction, and null a constant null1. After a minimum number null of iterations between two non-null frequency corrections are spent, being null a constant comprised between 1 and L. According to another variant the iterations of the recursive update are subdivided into an initial group with a higher K value for achieving fast convergence and a subsequent group with a lower K for achieving the required accuracy (FIG. 13).

公开(公告)号：US20030099313A1

公开(公告)日：2003-05-29

申请号：US10005778

申请日：2001-11-08

发明人： Yunxin Li ,  Xiaojing Huang

IPC分类号： H04L027/06

CPC分类号： H04L27/233 ,  H03H17/0266 ,  H04L27/2003 ,  H04L27/227

摘要： A filter bank (10) and receiver including the filter bank (10) that is designed for processing a baseband signal of a received continuous phase modulated signal S(t) with an integer modulation index. The filter bank (10) has outputs for providing a plurality of decision variable values (d1,d2,d3,d4) each representing a likelihood value of a symbol, from a group of predefined symbols that are likely to be present in the continuous phase modulated signal S(t). The filter bank 10 has filter units (12,14,16,18) each having an impulse response determined by a complex main pulse containing a majority of signal energy of one of the predefined symbols that is likely to be in the continuous phase modulated signal S(t).

摘要翻译： 滤波器组（10）和接收器，包括被设计用于处理具有整数调制指数的接收的连续相位调制信号S（t）的基带信号的滤波器组（10）。 滤波器组（10）具有输出，用于从可能存在于连续相中的预定符号组中提供各自表示符号的似然值的多个判定变量值（d1，d2，d3，d4） 调制信号S（t）。 滤波器组10具有滤波器单元（12,14,16,18），每个滤波器单元具有由复数主脉冲确定的脉冲响应，该复合主脉冲包含可能处于连续相位调制信号中的预定符号之一的信号能量的大部分 S（t）。

公开(公告)号：US20020181615A1

公开(公告)日：2002-12-05

申请号：US10119518

申请日：2002-04-10

发明人： Alexandr Kuzminskiy ,  Carlo Luschi ,  Paul Edward Strauch

IPC分类号： H04L027/06 ,  H03H007/40

CPC分类号： H04L27/233 ,  H04L2027/0055 ,  H04L2027/0095

摘要： A frequency estimator is provided for use in a receiver of packetized data. The frequency estimator determines the signal frequency error ({circumflex over (null)}o) with which a data packet has been received. It does this by relating data (gn) representative of some symbols to decisions (Sn) on those symbols. These symbols include not only training symbols (Nt) but also some information symbols (Nadd).

摘要翻译： 提供频率估计器用于分组化数据的接收机。 频率估计器确定已经接收到数据分组的信号频率误差（ƒo）。 它通过将代表某些符号的数据（gn）与这些符号上的决定（Sn）相关联来实现。 这些符号不仅包括训练符号（Nt），还包括一些信息符号（Nadd）。

公开(公告)号：US20020172294A1

公开(公告)日：2002-11-21

申请号：US09824282

申请日：2001-04-02

发明人： Jung-Fu Cheng

IPC分类号： H04L027/10

CPC分类号： H04L1/005 ,  H04L1/0066 ,  H04L1/0071 ,  H04L1/18 ,  H04L27/2075 ,  H04L27/233

摘要： Methods and systems for iterative demodulation of a message are provided. A first copy of the message is received to provide a first set of symbols associated with the message. A second copy of the message is received to provide a second set of symbols. The first copy is associated with a first interleaving pattern and the second copy is associated with a second interleaving pattern different from the first interleaving pattern. The first set of symbols and the second set of symbols are iteratively demodulated using extrinsic information associated with the first set of symbols for demodulation of the second set of symbols and extrinsic information associated with the second set of symbols for demodulation of the first set of symbols to provide a set of symbol estimates for the message. Transmit methods and systems for selective interleaving to generate the copies of the message in a retransmission based communication system are also provided.

摘要翻译： 提供了一种用于迭代解调消息的方法和系统。 接收消息的第一副本以提供与消息相关联的第一组符号。 接收消息的第二副本以提供第二组符号。 第一副本与第一交错模式相关联，并且第二副本与不同于第一交错模式的第二交织模式相关联。 使用与第一组符号相关联的外部信息对第一组符号和第二组符号进行迭代解调，以解调第二组符号，并且与第二组符号相关联的外在信息用于解调第一组符号 为消息提供一组符号估计。 还提供了用于选择性交错以在基于重传的通信系统中生成消息的副本的发送方法和系统。

公开(公告)号：US20020168032A1

公开(公告)日：2002-11-14

申请号：US10069741

申请日：2002-02-26

发明人： Delphine Legrand ,  Americo Brajal ,  Antoine Chouly

IPC分类号： H03D003/22

CPC分类号： H04L27/233 ,  H04L2027/0067

摘要： The invention relates to any receiver for MPSK (Mnull2n) modulation, in which an error correction device is used for correcting Tretter type frequency errors and, upstream of this device, a phase estimation device based on decisions made on the received symbols. When the frequency error is such that, based on a certain symbol, an error is made in the decision, this error is translated by a phase jump of 1 null null 2 n - 1 in the sequence of phase estimations obtained. The frequency estimation obtained is then inaccurate. A receiver according to the invention comprises means for calculating a phase sequence, called initial sequence, based on decisions made on symbols, and means for detecting and correcting phase jumps in this initial sequence, so as to supply a phase sequence, called final sequence, to said frequency error estimation means. Applications: Interactive data transmission systemnullnetwork head-ends.

摘要翻译： 本发明涉及用于MPSK（M = 2n）调制的任何接收机，其中纠错装置用于校正Tretter型频率误差，并且在该装置的上游，基于对接收到的符号作出的决定，相位估计装置。 当频率误差使得基于某个符号时，在判定中出现错误，该错误由 1 < / number>