公开(公告)号：US5504479A

公开(公告)日：1996-04-02

申请号：US473441

申请日：1995-06-07

申请人： Mark R. Doyle ,  Fuling Liu ,  Jorge O. Maxit

发明人： Mark R. Doyle ,  Fuling Liu ,  Jorge O. Maxit

IPC分类号： E21B47/12 ,  H04L25/49 ,  G01V1/00

CPC分类号： H04L25/4921 ,  E21B47/122

摘要： An apparatus for communicating signals from a well logging tool to a recording unit is disclosed. The logging tool includes a transmitter comprising a source of digital bits representing measurements made by the tool, an encoder connected to the source of digital bits for transforming groups of the digital bits into multivalued symbols, a first in-phase filter and a first quadrature filter connected to the encoder so that first coordinates of the symbols are filtered in the in-phase filter, second coordinates of the symbols are filtered in the quadrature filter, the filters having responses forming a Hilbert transform pair, a digital subtractor connected to the first filters for calculating a difference between outputs of the filters, and a digital-to-analog converter connected to the output of the subtractor for generating signals to be communicated to the recording unit over a communication channel.The recording unit includes a receiver comprising an analog-to-digital converter to receive and digitize signals from the communication channel, a second in-phase filter and a second quadrature filter connected to the analog-to-digital converter, the second filters respectively having substantially the same response characteristics as the first in-phase and quadrature filters, a decision feedback equalizer connected to the second filters for correcting timing and distortion errors in the signals from the logging tool and demodulating the multivalued symbols, and a decoder connected to the equalizer for converting demodulated multivalued symbols output from the equalizer into the groups of bits conducted to the encoder in the logging tool.

摘要翻译： 公开了一种用于将测井工具的信号传送到记录单元的装置。 记录工具包括发射机，包括表示由该工具进行的测量的数字位源;连接到数字位源的编码器，用于将数字位组的组变换为多值符号;第一同相滤波器和第一正交滤波器 连接到编码器，使得符号的第一坐标在同相滤波器中被滤波，符号的第二坐标在正交滤波器中被滤波，滤波器具有形成希尔伯特变换对的响应，连接到第一滤波器的数字减法器 用于计算滤波器的输出之间的差异，以及连接到减法器的输出的数模转换器，用于通过通信信道产生要传送到记录单元的信号。 记录单元包括一个接收机，包括一个模拟 - 数字转换器，用于接收和数字化来自通信信道的信号，第二同相滤波器和连接到模拟 - 数字转换器的第二正交滤波器，第二滤波器分别具有 与第一同相和正交滤波器基本相同的响应特性，连接到第二滤波器的判决反馈均衡器，用于校正来自测井工具的信号中的定时和失真误差并解调多值符号，以及连接到均衡器的解码器 用于将从均衡器输出的解调多值符号转换成在测井工具中传送到编码器的位组。

公开(公告)号：US06580696B1

公开(公告)日：2003-06-17

申请号：US09406211

申请日：1999-09-27

申请人： Herbert M. K. Chen ,  Fuling Liu

发明人： Herbert M. K. Chen ,  Fuling Liu

IPC分类号： H04M908

CPC分类号： H04B3/23

摘要： The present invention relates to a system and method for canceling echoes from telecommunications networks by providing a multi-adaptation echo canceller. Unlike conventional TDM echo cancellers, the present invention uses at least two echo cancellers arranged in a novel manner to cancel echoes generated by a voice packet associated with an IP network or the like. The present invention further provides a double adaptation echo canceller that transfers coefficients from a first echo canceller to a second echo canceller. The present system compares the single and double adaptation echo error signals and selects the echo canceller with the smaller error signal. This process is continuously repeated so that the system can select the optimal echo canceller for canceling echoes for each voice block/packet. The present invention can be implemented with any number of echo cancellers so long as the each block or packet can be processed within a specified time frame.

摘要翻译： 本发明涉及通过提供多适应回波消除器来消除来自电信网络的回波的系统和方法。 与传统的TDM回波消除器不同，本发明使用以新颖的方式布置的至少两个回波消除器来消除由与IP网络等相关联的语音分组产生的回波。 本发明还提供一种双重适应回波消除器，其将系数从第一回波消除器传送到第二回波消除器。 本系统比较单和双适应回波误差信号，并选择具有较小误差信号的回波消除器。 该过程被连续重复，使得系统可以选择用于消除每个语音块/分组的回波的最佳回波消除器。 本发明可以用任何数量的回波消除器实现，只要每个块或分组可以在指定的时间帧内被处理。