公开(公告)号：US06570917B1

公开(公告)日：2003-05-27

申请号：US09338664

申请日：1999-06-22

申请人： Yhean-Sen Lai ,  Zhenyu Wang ,  Jiangtao Xi ,  Bahman Barazesh

发明人： Yhean-Sen Lai ,  Zhenyu Wang ,  Jiangtao Xi ,  Bahman Barazesh

IPC分类号： H03K5159

CPC分类号： H04L5/143 ,  H04L25/03146 ,  H04L25/4927 ,  H04L2025/03363 ,  H04L2025/0349 ,  H04L2025/03503 ,  H04L2025/0377 ,  H04L2025/03783

摘要： Analog modems are enabled to better learn the slicing levels employed at the interface to a digital transmission network by reducing the effects of the various noise sources. Initially a training sequence is received to preliminarily adjust the analog modem's equalizer. Thereafter, a special training sequence, protected against intersymbol interference, is employed to collect samples of each slicing level, to ascertain the least mean squared value of each slicing level from the received samples and to obtain the channel's impulse response at each slicing level. To mitigate the effects of robbed bit signaling that may be employed in the digital transmission network, an array of slicers is provided to determine which bit position is being robbed and to base level learning on samples obtained from the non-robbed positions.

摘要翻译： 使模拟调制解调器能够通过减少各种噪声源的影响，更好地了解在数字传输网络的接口处采用的切片级别。 最初接收训练序列以初步调整模拟调制解调器的均衡器。 此后，采用保护码间干扰的特殊训练序列来收集每个限幅电平的样本，以便从接收到的采样中确定每个限幅电平的最小均方值，并在每个限幅电平下获得信道的脉冲响应。 为了减轻可能在数字传输网络中使用的抢占位信令的影响，提供了一系列限幅器，以确定哪个位位置被抢走，并从非抢占位置获得的样本的基础级学习。

公开(公告)号：US06600780B1

公开(公告)日：2003-07-29

申请号：US09338134

申请日：1999-06-22

申请人： Zhenyu Wang ,  Yhean-Sen Lai ,  Jiangtao Xi ,  Bahman Barazesh

发明人： Zhenyu Wang ,  Yhean-Sen Lai ,  Jiangtao Xi ,  Bahman Barazesh

IPC分类号： H03H2100

CPC分类号： H04L25/03146 ,  H04L5/143 ,  H04L25/4927 ,  H04L2025/03503 ,  H04L2025/0377

摘要： Analog modems are enabled to better learn the slicing levels employed at the interface to a digital transmission network by reducing the effects of the various noise sources. Initially a training sequence is received to preliminarily adjust the analog modem's equalizer. Thereafter, a special training sequence, protected against intersymbol interference, is employed to collect samples of each slicing level, to ascertain the least mean squared value of each slicing level from the received samples and to obtain the channel's impulse response at each slicing level. Depending on the means squared error (MSE) between the input and the output of the slicer, the slicer tables continue to be updated, and the feed-forward and feed-backward equalizer filters are selectively adjusted in accordance with the channel impulse response ascertained at each of the slicing levels.

摘要翻译： 使模拟调制解调器能够通过减少各种噪声源的影响，更好地了解在数字传输网络的接口处采用的切片级别。 最初接收训练序列以初步调整模拟调制解调器的均衡器。 此后，采用保护码间干扰的特殊训练序列来收集每个限幅电平的样本，以便从接收到的采样中确定每个限幅电平的最小均方值，并在每个限幅电平下获得信道的脉冲响应。 根据切片器的输入和输出之间的均方误差（MSE），切片器表继续更新，并且前馈和反馈均衡器滤波器根据在 每个切片级别。

公开(公告)号：US06185250B2

公开(公告)日：2001-02-06

申请号：US09337687

申请日：1999-06-22

申请人： Zhenyu Wang ,  Yhean-Sen Lai ,  Jiangtao Xi ,  Bahman Barazesh

发明人： Zhenyu Wang ,  Yhean-Sen Lai ,  Jiangtao Xi ,  Bahman Barazesh

IPC分类号： H04B138

CPC分类号： H04L25/4927 ,  H04L5/143 ,  H04L25/03146 ,  H04L2025/03363 ,  H04L2025/0349 ,  H04L2025/03503 ,  H04L2025/0377 ,  H04L2025/03783

摘要： Analog modems are enabled to better learn the slicing levels employed at the interface to a digital transmission network by reducing the effects of the various noise sources. Initially a training sequence is received to preliminarily adjust the analog modem's equalizer. Thereafter, a special training sequence, protected against intersymbol interference, is employed to collect samples of each slicing level, to ascertain the least mean squared value of each slicing level from the received samples and to obtain the channel's impulse response at each slicing level. Thereafter, the analog modem's equalizer may be fine tuned in accordance with the channel impulse response ascertained at each slicing level.

摘要翻译： 使模拟调制解调器能够通过减少各种噪声源的影响，更好地了解在数字传输网络的接口处采用的切片级别。 最初接收训练序列以初步调整模拟调制解调器的均衡器。 此后，采用保护码间干扰的特殊训练序列来收集每个限幅电平的样本，以便从接收到的采样中确定每个限幅电平的最小均方值，并在每个限幅电平下获得信道的脉冲响应。 此后，模拟调制解调器的均衡器可以根据在每个切片级别确定的信道脉冲响应进行微调。

公开(公告)号：US06771695B1

公开(公告)日：2004-08-03

申请号：US09364411

申请日：1999-07-30

申请人： Raja Banerjea ,  Bahman Barazesh ,  Yhean-Sen Lai ,  Kannan Rajamani ,  Geoffrey L. Smith

发明人： Raja Banerjea ,  Bahman Barazesh ,  Yhean-Sen Lai ,  Kannan Rajamani ,  Geoffrey L. Smith

IPC分类号： H04B138

CPC分类号： H04L25/05 ,  H04L27/2608

摘要： A DMT signal conforming to a first DMT standard (e.g., the full-rate G.dmt standard based on 255 tones) is sampled at a sampling rate for the first DMT standard, filtered to attenuate a subset of the tones of the first DMT standard (e.g., all G.dmt tones above tone #127), and subsampled (e.g., 2:1) to provide a subsampled, filtered signal that can be further processed using components designed to operate under a second, different DMT standard (e.g., the half-rate G.lite standard based on 127 tones). As such, a conventional half-rate G.lite DMT transceiver can be modified (e.g., by changing the downstream sampling rate from 1.104 MHz to 2.208 MHz and adding an appropriate low-pass filter and decimator) for configuration in a full-rate G.dmt DMT system. The filtering and subsampling ensure that a downstream signal (even if it is a full-rate DMT initialization or synchronization signal containing tones above tone #127) can successfully be further processed using conventional half-rate DMT transceiver components, which are less complex and less expensive than those of full-rate DMT transceivers, thereby enabling the use of relatively inexpensive consumer personal equipment (CPE) in existing distributed full-rate DMT telecommunications systems.

摘要翻译： 符合第一DMT标准（例如，基于255个音调的全速率G.dmt标准）的DMT信号以对于第一DMT标准的采样率进行采样，被滤波以衰减第一DMT标准的音调的子集 （例如，音调＃127之上的所有G.dmt音调），并且被二次采样（例如，2:1）以提供可以使用被设计为在第二种不同DMT标准下操作的组件进一步处理的子采样滤波信号（例如， 基于127个音调的半速率G.lite标准）。 因此，传统的半速率G.lite DMT收发器可以被修改（例如，通过将下行采样率从1.104MHz改变到2.208MHz并添加适当的低通滤波器和抽取器）来配置全速率G .dmt DMT系统。 滤波和二次采样确保下行信号（即使是全速率DMT初始化或包含音调＃127以上的音频的同步信号）也可以使用传统的半速率DMT收发器组件进行进一步处理，这些组件不太复杂和较少 比全速率DMT收发器更昂贵，从而能够在现有的分布式全速率DMT电信系统中使用相对便宜的消费者个人设备（CPE）。

公开(公告)号：US06240128B1

公开(公告)日：2001-05-29

申请号：US09096425

申请日：1998-06-11

申请人： Raja Banerjea ,  Bahman Barazesh ,  Yhean-Sen Lai ,  Kannan Rajamani

发明人： Raja Banerjea ,  Bahman Barazesh ,  Yhean-Sen Lai ,  Kannan Rajamani

IPC分类号： H04L516

CPC分类号： H04B3/23 ,  H04L5/16

摘要： A so-called post equalization echo canceler is utilized in conjunction with transmitter and receiver data timing synchronization to enhance tracking of the echo path impulse response and convergence of the transversal filter in the post equalization echo canceler. This is realized by employing the equalization error in the receiver to adapt coefficients of the post equalization echo canceler transversal filter, in conjunction, with the transmitter and receiver data timing synchronization. The timing synchronization is realized by using sample rate conversion of the transmit sample rate to the receive sample rate and, in one example, variable phase interpolation of the converted timing signal. The receiver timing is recovered, and a phase error signal generated by the timing recovery unit is advantageously employed to adjust a variable phase interpolator in the receiver and a variable phase interpolator in a path supplying the transmitter signal to an input of the post equalization echo canceler. This insures that both the adaptive transversal filter of the post equalization echo canceler and a transversal filter in an equalizer in the receiver are operating on data having the same timing. In this example, the timing is that of the received data signal. In an embodiment of the invention, the post equalization echo canceler is utilized in conjunction with a so-called conventional, e.g., a primary, echo canceler. The conventional echo canceler is employed before the equalizer to cancel a major portion of any echo signal, while the post equalization echo canceler is employed after the equalizer to cancel residual echo signals caused primarily by drift in the hybrid network. To this end, the conventional echo canceler is “trained” during the initial half-duplex operation of the modem and, then, updating of its impulse response is inhibited, while the post equalization echo canceler is allowed to continue adapting.

摘要翻译： 所谓后置均衡回波消除器与发射机和接收机数据定时同步结合使用，以增强跟踪均衡回波消除器中的回波路径脉冲响应和横向滤波器的收敛。 这通过在接收机中采用均衡误差来实现，以使后均衡回波消除器横向滤波器的系数与发射机和接收机的数据定时同步相结合。 通过使用发送采样率的采样率转换为接收采样率，并且在一个示例中，转换的定时信号的可变相位插值来实现定时同步。 接收器定时被恢复，并且有利地采用由定时恢复单元产生的相位误差信号来调整接收机中的可变相位内插器和将发射机信号提供给后均衡回波消除器的输入的路径中的可变相位内插器 。 这确保后均衡回波消除器的自适应横向滤波器和接收机中的均衡器中的横向滤波器对具有相同定时的数据进行操作。 在该示例中，定时是所接收的数据信号的时序。 在本发明的一个实施例中，后均衡回波消除器与所谓常规的，例如主回波消除器结合使用。 在均衡器之前采用传统的回波消除器来消除任何回波信号的主要部分，而在均衡器之后采用后均衡回波消除器来消除主要由混合网络中的漂移引起的残余回波信号。 为此，传统的回波消除器在调制解调器的初始半双工操作期间被“训练”，然后，抑制其脉冲响应的更新，同时允许后均衡回波消除器继续适配。

公开(公告)号：US08391384B2

公开(公告)日：2013-03-05

申请号：US13085525

申请日：2011-04-13

申请人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

发明人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

IPC分类号： H04K27/00

CPC分类号： H04L27/0008 ,  H03G3/3068 ,  H03G3/3078 ,  H04L27/2649

摘要： An improved multi-channel receiver for satellite broadcast applications or the like. In an exemplary embodiment, a primary AGC loop controls an analog sub-receiver adapted to simultaneously receive multiple signals. Multiple digital demodulators, coupled to the sub-receiver, demodulate the multiple received signals. Multiple secondary AGC loops, one for each received signal, compensate for variations in demodulated signal strengths caused by the primary AGC loop. A feed-forward AGC compensation technique generates scalar control values for scaling the demodulated signals before the demodulated signals are processed by the secondary AGC loops. This at least partially compensates for gain variations caused by the primary AGC, reducing received signal drop-outs before the secondary AGC loops can compensate for the gain variations. Because of systemic delays in the sub-receiver and the demodulators, the scalar control values are independently timed to be coincident with the variations in the demodulated signal strengths caused by the primary AGC loop.

摘要翻译： 用于卫星广播应用的改进的多频道接收机等。 在示例性实施例中，主AGC环路控制适于同时接收多个信号的模拟子接收机。 耦合到子接收机的多个数字解调器解调多个接收信号。 多个次级AGC环路，每个接收信号一个补偿由主AGC环路引起的解调信号强度的变化。 前馈AGC补偿技术产生标量控制值，用于在解调后的信号由次级AGC环路处理之前缩放解调信号。 这至少部分地补偿由主AGC引起的增益变化，在次级AGC环路可以补偿增益变化之前减少接收信号丢失。 由于子接收机和解调器中的系统延迟，标量控制值被独立地定时以与由主AGC环路引起的解调信号强度的变化一致。

公开(公告)号：US07809343B2

公开(公告)日：2010-10-05

申请号：US11796006

申请日：2007-04-25

申请人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

发明人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

IPC分类号： H04B7/00 ,  H04M1/00

CPC分类号： H04L27/2647 ,  H04L5/0007

摘要： An improved multi-channel receiver for satellite broadcast applications or the like. In an exemplary embodiment, an AGC loop, under the control of an AGC processor, controls the gain of an analog sub-receiver adapted to simultaneously receive multiple signals to achieve a desired AGC setpoint signal intensity from the sub-receiver. Multiple digital demodulators, coupled to the sub-receiver by an analog-to-digital converter (ADC), demodulate the multiple received signals. The AGC controller, based upon which of the received signals are being demodulated, selects the desired AGC setpoint from a table of setpoints. The AGC controller may also provide selective power control to circuitry in the receiver and select the resolution of the ADC. The controller updates the AGC loop with step values selected from a group of values by an AGC control algorithm. Different groups of step values may be used by the controller depending on whether the signals are fading or not.

公开(公告)号：US20080267326A1

公开(公告)日：2008-10-30

申请号：US11796006

申请日：2007-04-25

申请人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

发明人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

IPC分类号： H04L27/08

CPC分类号： H04L27/2647 ,  H04L5/0007

摘要： An improved multi-channel receiver for satellite broadcast applications or the like. In an exemplary embodiment, an AGC loop, under the control of an AGC processor, controls the gain of an analog sub-receiver adapted to simultaneously receive multiple signals to achieve a desired AGC setpoint signal intensity from the sub-receiver. Multiple digital demodulators, coupled to the sub-receiver by an analog-to-digital converter (ADC), demodulate the multiple received signals. The AGC controller, based upon which of the received signals are being demodulated, selects the desired AGC setpoint from a table of setpoints. The AGC controller may also provide selective power control to circuitry in the receiver and select the resolution of the ADC. The controller updates the AGC loop with step values selected from a group of values by an AGC control algorithm. Different groups of step values may be used by the controller depending on whether the signals are fading or not.

公开(公告)号：US20110188489A1

公开(公告)日：2011-08-04

申请号：US13085525

申请日：2011-04-13

申请人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

发明人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

IPC分类号： H04B1/06 ,  H04J1/00

CPC分类号： H04L27/0008 ,  H03G3/3068 ,  H03G3/3078 ,  H04L27/2649

摘要： An improved multi-channel receiver for satellite broadcast applications or the like. In an exemplary embodiment, a primary AGC loop controls an analog sub-receiver adapted to simultaneously receive multiple signals. Multiple digital demodulators, coupled to the sub-receiver, demodulate the multiple received signals. Multiple secondary AGC loops, one for each received signal, compensate for variations in demodulated signal strengths caused by the primary AGC loop. A feed-forward AGC compensation technique generates scalar control values for scaling the demodulated signals before the demodulated signals are processed by the secondary AGC loops. This at least partially compensates for gain variations caused by the primary AGC, reducing received signal drop-outs before the secondary AGC loops can compensate for the gain variations. Because of systemic delays in the sub-receiver and the demodulators, the scalar control values are independently timed to be coincident with the variations in the demodulated signal strengths caused by the primary AGC loop.

摘要翻译： 用于卫星广播应用的改进的多频道接收机等。 在示例性实施例中，主AGC环路控制适于同时接收多个信号的模拟子接收机。 耦合到子接收机的多个数字解调器解调多个接收信号。 多个次级AGC环路，每个接收信号一个补偿由主AGC环路引起的解调信号强度的变化。 前馈AGC补偿技术产生标量控制值，用于在解调后的信号由次级AGC环路处理之前缩放解调信号。 这至少部分地补偿由主AGC引起的增益变化，在次级AGC环路可以补偿增益变化之前减少接收信号丢失。 由于子接收机和解调器中的系统延迟，标量控制值被独立地定时以与由主AGC环路引起的解调信号强度的变化一致。

公开(公告)号：US07978773B2

公开(公告)日：2011-07-12

申请号：US11648702

申请日：2006-12-29

申请人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

发明人： Yhean-Sen Lai ,  Jie Song ,  Zhenyu Wang ,  Jinguo Yu

IPC分类号： H04K27/00

CPC分类号： H04L27/0008 ,  H03G3/3068 ,  H03G3/3078 ,  H04L27/2649

摘要： An improved multi-channel receiver for satellite broadcast applications or the like. In an exemplary embodiment, a primary AGC loop controls an analog sub-receiver adapted to simultaneously receive multiple signals. Multiple digital demodulators, coupled to the sub-receiver, demodulate the multiple received signals. Multiple secondary AGC loops, one for each received signal, compensate for variations in demodulated signal strengths caused by the primary AGC loop. A feed-forward AGC compensation technique generates scalar control values for scaling the demodulated signals before the demodulated signals are processed by the secondary AGC loops. This at least partially compensates for gain variations caused by the primary AGC, reducing received signal drop-outs before the secondary AGC loops can compensate for the gain variations. Because of systemic delays in the sub-receiver and the demodulators, the scalar control values are independently timed to be coincident with the variations in the demodulated signal strengths caused by the primary AGC loop.

摘要翻译： 用于卫星广播应用的改进的多频道接收机等。 在示例性实施例中，主AGC环路控制适于同时接收多个信号的模拟子接收机。 耦合到子接收机的多个数字解调器解调多个接收信号。 多个次级AGC环路，每个接收信号一个补偿由主AGC环路引起的解调信号强度的变化。 前馈AGC补偿技术产生标量控制值，用于在解调后的信号由次级AGC环路处理之前缩放解调信号。 这至少部分地补偿由主AGC引起的增益变化，在次级AGC环路可以补偿增益变化之前减少接收信号丢失。 由于子接收机和解调器中的系统延迟，标量控制值被独立地定时以与由主AGC环路引起的解调信号强度的变化一致。