公开(公告)号：US06917629B1

公开(公告)日：2005-07-12

申请号：US09152063

申请日：1998-09-11

申请人： Rajaram Ramésh ,  Gregory E. Bottomley

发明人： Rajaram Ramésh ,  Gregory E. Bottomley

IPC分类号： H04L1/00 ,  H04L1/08 ,  H04J3/06

CPC分类号： H04L1/0038 ,  H04L1/0013 ,  H04L1/0046 ,  H04L1/0054 ,  H04L1/0061 ,  H04L1/08

摘要： An improved system and method for rate detection of transmitted signals is disclosed for use in a IS-95 CDMA downlink. For each speech frame, one of four possible bit rates is used to encode the frame according to the standard. The present invention describes a receiver and various processes that are able to detect which rate was sent without the aid of flag bits or other mode indication information. According to various embodiments of the invention different rate detection processes which can exploit additional code information, such as CRC checks and convolutional coding, are disclosed.

摘要翻译： 公开了用于IS-95 CDMA下行链路中的用于传输信号的速率检测的改进的系统和方法。 对于每个语音帧，四种可能的比特率之一用于根据标准对帧进行编码。 本发明描述了一种接收机和能够检测哪个速率被发送而不借助于标志位或其他模式指示信息的各种过程。 根据本发明的各种实施例，公开了可以利用附加码信息（诸如CRC校验和卷积编码）的不同速率检测过程。

公开(公告)号：US06487255B1

公开(公告)日：2002-11-26

申请号：US09143754

申请日：1998-08-31

申请人： Hüseyin Arslan ,  Gregory E. Bottomley ,  Rajaram Ramésh

发明人： Hüseyin Arslan ,  Gregory E. Bottomley ,  Rajaram Ramésh

IPC分类号： H04L512

CPC分类号： H04L25/03184 ,  H04L25/03318 ,  H04L2025/03375

摘要： Methods and systems are provided which generate hard and soft values from signal samples of a differentially encoded signal by estimating channel coefficients associated with the received signal and determining metrics for each possible symbol pair which indicate the probability of a possible coherent symbol pair being encoded in the signal samples using the estimated channel coefficients and the signal samples. Soft values associated with differential bits or differential symbols encoded in the samples of the signal are then generated based on the determined metrics.

摘要翻译： 提供了通过估计与接收信号相关联的信道系数并确定每个可能符号对的度量的方法和系统，其通过差分编码信号的信号样本产生硬和软值，其指示可能的相干符号对在 信号样本使用估计的信道系数和信号样本。 然后基于所确定的度量来生成与信号样本中编码的差分比特或差分符号相关联的软值。

公开(公告)号：US06411649B1

公开(公告)日：2002-06-25

申请号：US09175699

申请日：1998-10-20

申请人： Hüseyin Arslan ,  Rajaram Ramésh

发明人： Hüseyin Arslan ,  Rajaram Ramésh

IPC分类号： H03H730

CPC分类号： H04L25/0212 ,  H04L7/04 ,  H04L25/0228

摘要： Methods and systems are provided which utilize pilots in an information sequence to periodically retrain a channel estimator. Thus, a channel tracker may be synchronized using a synchronization sequence and then periodically retrained using known pilot symbols. Furthermore, the utilization of pilots may allow for the detection of errors in previous channel estimates. When errors are detected, a new channel estimate may be used based on the retraining using the pilot symbols and, optionally, previous errors in symbol estimation may be corrected. Thus, by retraining based on pilot symbols, the propagation of errors may be reduced.

摘要翻译： 提供了利用信息序列中的导频来定期重新训练信道估计器的方法和系统。 因此，可以使用同步序列来同步信道跟踪器，然后使用已知的导频符号周期性地重新训练。 此外，导频的利用可以允许检测先前信道估计中的误差。 当检测到错误时，可以基于使用导频符号的再培训来使用新的信道估计，并且可选地，可以校正符号估计中的先前错误。 因此，通过基于导频符号的再训练，可以减少误差的传播。