公开(公告)号：US07203227B1

公开(公告)日：2007-04-10

申请号：US10294048

申请日：2002-11-14

申请人： Bruce J. Currivan ,  Ravi Bhaskaran ,  Thomas J. Kolze ,  Kevin Lee Miller ,  Jeffrey S. Putnam ,  Fang Lu ,  Tak K. Lee ,  Thuji S. Lin ,  Loke Kun Tan ,  Gopal Triplicane Venkatesan ,  Hsin-An Liu ,  Jonathan S. Min ,  James P. Cavallo

发明人： Bruce J. Currivan ,  Ravi Bhaskaran ,  Thomas J. Kolze ,  Kevin Lee Miller ,  Jeffrey S. Putnam ,  Fang Lu ,  Tak K. Lee ,  Thuji S. Lin ,  Loke Kun Tan ,  Gopal Triplicane Venkatesan ,  Hsin-An Liu ,  Jonathan S. Min ,  James P. Cavallo

IPC分类号： H04B1/38

CPC分类号： H04L12/2801

摘要： All digital reference frequency locking. An all digital approach is provided for operation within one or more CMs within a cable modem communication system to lock the upstream of the one or more CMs to the downstream symbol clock provided from a CMTS. The locking of the CM's upstream may be performed using one of at least three different functions: (1) Locking the upstream symbol clock phase to the downstream symbol clock phase, (2) Locking the downstream symbol clock phase to the headend reference clock phase (typically 10.24 MHz or integer multiple thereof), and (3) Locking the upstream carrier frequency to the downstream symbol clock frequency. The all-digital techniques for supporting all digital reference frequency locking functionality provide high performance to support S-CDMA and other synchronous modulation techniques.

摘要翻译： 全数字参考频率锁定。 提供全数字方法以在电缆调制解调器通信系统内的一个或多个CM内操作，以将一个或多个CM的上游锁定到从CMTS提供的下游符号时钟。 CM的上游的锁定可以使用至少三种不同的功能中的一种执行：（1）将上游符号时钟相位锁定到下游符号时钟相位，（2）将下游符号时钟相位锁定到前端参考时钟相位 通常为10.24MHz或其整数倍），以及（3）将上游载波频率锁定到下游符号时钟频率。 用于支持所有数字参考频率锁定功能的全数字技术提供了高性能以支持S-CDMA和其他同步调制技术。

公开(公告)号：US07010062B2

公开(公告)日：2006-03-07

申请号：US09826969

申请日：2001-04-04

申请人： Robindra B. Joshi ,  Jeffrey S. Putnam ,  Thuji S. Lin ,  Paul T. Yang

发明人： Robindra B. Joshi ,  Jeffrey S. Putnam ,  Thuji S. Lin ,  Paul T. Yang

IPC分类号： H04L27/14 ,  H04L27/22

CPC分类号： H04L27/152 ,  H04L27/2602 ,  H04L27/261 ,  H04L27/2657 ,  H04L27/2675 ,  H04L2027/0028 ,  H04L2027/0055 ,  H04L2027/0067 ,  H04L2027/0069 ,  H04L2027/0083

摘要： A method of compensating for carrier frequency and phase errors of a received multi-carrier modulated signal. The received multi-carrier signal including modulated carriers for transmitting known data and unmodulated carriers for error correction, comprising, time domain down converting the received multi-carrier signal to base-band to provide a down-converted signal, the down-converted signal including a plurality of modulated carriers for transmitting known data and unmodulated carriers for error correction. Sampling an unmodulated carrier of the down-converted signal to provide received data samples. Providing a reference signal derived from the unmodulated carrier of the down-converted signal. And, estimating phase errors from a phase difference between the ummodulated carrier and the reference signal derived from the unmodulated carrier of the down-converted signal to provide a plurality of received sample phase error estimates for each modulated carrier.

公开(公告)号：US08537934B2

公开(公告)日：2013-09-17

申请号：US11331520

申请日：2006-01-12

申请人： Robindra B. Joshi ,  Jeffrey S. Putnam ,  Thuji S. Lin ,  Paul T. Yang

发明人： Robindra B. Joshi ,  Jeffrey S. Putnam ,  Thuji S. Lin ,  Paul T. Yang

IPC分类号： H04L27/00

CPC分类号： H04L27/152 ,  H04L27/2602 ,  H04L27/261 ,  H04L27/2657 ,  H04L27/2675 ,  H04L2027/0028 ,  H04L2027/0055 ,  H04L2027/0067 ,  H04L2027/0069 ,  H04L2027/0083

摘要： A method of compensating for carrier frequency and phase errors of a received multi-carrier modulated signal. The received multi-carrier signal including modulated carriers for transmitting known data and unmodulated carriers for error correction, comprising, time domain down converting the received multi-carrier signal to base-band to provide a down-converted signal, the down-converted signal including a plurality of modulated carriers for transmitting known data and unmodulated carriers for error correction. Sampling an unmodulated carrier of the down-converted signal to provide received data samples. Providing a reference signal derived from the unmodulated carrier of the down-converted signal. And, estimating phase errors from a phase difference between the ummodulated carrier and the reference signal derived from the unmodulated carrier of the down-converted signal to provide a plurality of received sample phase error estimates for each modulated carrier.

公开(公告)号：US06671342B2

公开(公告)日：2003-12-30

申请号：US10288833

申请日：2002-11-06

申请人： Thuji S. Lin ,  Tian-Min Liu ,  Stephen E. Krafft

发明人： Thuji S. Lin ,  Tian-Min Liu ,  Stephen E. Krafft

IPC分类号： H03D322

CPC分类号： H04N5/21 ,  H04B1/68 ,  H04L25/03057 ,  H04L27/02 ,  H04L27/066 ,  H04L27/2273 ,  H04L27/3427 ,  H04L27/3827 ,  H04L2025/03382 ,  H04L2025/0342 ,  H04L2025/0349 ,  H04L2025/03503 ,  H04L2027/0032 ,  H04L2027/0042 ,  H04L2027/0057 ,  H04L2027/0067 ,  H04L2027/0087 ,  H04N5/211 ,  H04N5/44 ,  H04N5/4401 ,  H04N5/455 ,  H04N5/46 ,  H04N11/002

摘要： Improved carrier recovery, symbol timing, and carrier phase tracking systems and methods suitable for use in connection with a dual-mode QAM/VSB receiver system are disclosed. Carrier and phase recovery systems operate on complex signals representing symbols having the same time stamp for each phase error term. in-phase signals are sampled twice a symbol at the in-phase symbol sampling time and at the quadrature-phase symbol sampling time. The signals are de-multiplexed to generate I and XI data streams, where I represents the in-phase sampling time signals and XI represents mid-symbol point sample times. A similar procedure is carrier out on quadrature-phase signals. When the in-phase signal is de-multiplexed to generate a symbol I, the quadrature-phase signal is de-multiplexed to generate its mid-symbol point XQ. Both I and Q are decoded in a decision device to define a symbol error term, which is combined with the opposite mid-symbol signal to define a phase error term PI and PQ for each rail. In both cases, the symbol (I) decision (Î), and mid-symbol (XQ) in each phase error term (PI) computation will have the same prime index.

公开(公告)号：US07327819B2

公开(公告)日：2008-02-05

申请号：US10687172

申请日：2003-10-16

申请人： Thuji S. Lin ,  Tian-Min Liu ,  Stephen E. Krafft

发明人： Thuji S. Lin ,  Tian-Min Liu ,  Stephen E. Krafft

IPC分类号： H03D3/24

CPC分类号： H04N5/21 ,  H04B1/68 ,  H04L25/03057 ,  H04L27/02 ,  H04L27/066 ,  H04L27/2273 ,  H04L27/3427 ,  H04L27/3827 ,  H04L2025/03382 ,  H04L2025/0342 ,  H04L2025/0349 ,  H04L2025/03503 ,  H04L2027/0032 ,  H04L2027/0042 ,  H04L2027/0057 ,  H04L2027/0067 ,  H04L2027/0087 ,  H04N5/211 ,  H04N5/44 ,  H04N5/4401 ,  H04N5/455 ,  H04N5/46 ,  H04N11/002

摘要： A carrier recovery, symbol timing, and carrier phase tracking systems and methods suitable for use in connection with a dual-mode QAM/VSB receiver system. In-phase signals are sampled twice a symbol at the in-phase symbol sampling time and at the quadrature-phase symbol sampling time. The signals are de-multiplexed to generate I and XI data streams, where I represents the in-phase sampling time signals and XI represents mid-symbol point sample times. A similar procedure is carrier out on quadrature-phase signals. When the in-phase signal is de-multiplexed to generate a symbol I, the quadrature-phase signal is de-multiplexed to generate its mid-symbol point XQ. Both I and Q are decoded to define a symbol error term, which is combined with the opposite mid-symbol signal to define a phase error term PI and PQ for each rail.

摘要翻译： 载波恢复，符号定时和载波相位跟踪系统和适用于双模QAM / VSB接收机系统的方法。 在同相符号采样时间和正交相位符号采样时间，将同相信号采样两次符号。 这些信号被去多路复用以产生I和X I I数据流，其中I表示同相采样时间信号，X I I表示中间符号点采样时间。 类似的过程是正交相位信号的载波。 当同相信号被去多路复用以产生符号I时，正交相位信号被去多路复用以产生其中间符号点X Q Q。 对I和Q进行解码以定义符号误差项，其与相对的中间码元信号相组合，以对每个信号定义相位误差项P 1和Q 2 轨。

公开(公告)号：US06493409B1

公开(公告)日：2002-12-10

申请号：US09433732

申请日：1999-11-03

申请人： Thuji S. Lin ,  Tian-Min Liu ,  Stephen E. Krafft

发明人： Thuji S. Lin ,  Tian-Min Liu ,  Stephen E. Krafft

IPC分类号： H03D322

CPC分类号： H04N5/21 ,  H04B1/68 ,  H04L25/03057 ,  H04L27/02 ,  H04L27/066 ,  H04L27/2273 ,  H04L27/3427 ,  H04L27/3827 ,  H04L2025/03382 ,  H04L2025/0342 ,  H04L2025/0349 ,  H04L2025/03503 ,  H04L2027/0032 ,  H04L2027/0042 ,  H04L2027/0057 ,  H04L2027/0067 ,  H04L2027/0087 ,  H04N5/211 ,  H04N5/44 ,  H04N5/4401 ,  H04N5/455 ,  H04N5/46 ,  H04N11/002

摘要： Improved carrier recovery, symbol timing, and carrier phase tracking systems and methods suitable for use in connection with a dual-mode QAM/VSB receiver system are disclosed. Carrier and phase recovery systems operate on complex signals representing symbols having the same time stamp for each phase error term. in-phase signals are sampled twice a symbol at the in-phase symbol sampling time and at the quadrature-phase symbol sampling time. The signals are de-multiplexed to generate I and XI data streams, where I represents the in-phase sampling time signals and XI represents mid-symbol point sample times. A similar procedure is carrier out on quadrature-phase signals. When the in-phase signal is de-multiplexed to generate a symbol I, the quadrature-phase signal is de-multiplexed to generate its mid-symbol point XQ. Both I and Q are decoded in a decision device to define a symbol error term, which is combined with the opposite mid-symbol signal to define a phase error term PI and PQ for each rail. In both cases, the symbol (I) decision (Î), and mid-symbol (XQ) in each phase error term (PI) computation will have the same prime index.

摘要翻译： 公开了改进的载波恢复，符号定时以及适用于双模QAM / VSB接收机系统的载波相位跟踪系统和方法。 载波和相位恢复系统对表示每个相位误差项具有相同时间戳的符号的复数信号进行操作。 在同相符号采样时间和正交相位符号采样时间，将同相信号采样两次符号。 信号被去多路复用以产生I和XI数据流，其中I表示同相采样时间信号，XI表示中间符号点采样时间。 类似的过程是正交相位信号的载波。 当同相信号被去多路复用以产生符号I时，正交相位信号被去多路复用以产生其中间符号点XQ。 在决策装置中对I和Q两者进行解码，以定义符号误差项，该符号误差项与相反的中间码元信号组合，以定义每个轨道的相位误差项PI和PQ。 在这两种情况下，每个相位误差项（PI）计算中的符号（I）决策（Î）和中间符号（XQ）将具有相同的素数指数。