公开(公告)号：US5818378A

公开(公告)日：1998-10-06

申请号：US872272

申请日：1997-06-10

申请人： Yi Cheng ,  Zhenhua Liu ,  Thomas Jefferson Ronaldue

发明人： Yi Cheng ,  Zhenhua Liu ,  Thomas Jefferson Ronaldue

IPC分类号： H04B3/04 ,  G01B7/02 ,  H03M1/36 ,  H04B10/14 ,  H03M1/00

CPC分类号： G01B7/02 ,  H03M1/367

摘要： A cable length estimation circuit for receiving an input MLT-3 signal provided through an arbitrary length cable and providing a control signal to an equalizer indicating the estimated length of the cable enabling the equalizer to compensate for distortion of the MLT-3 signal resulting from the cable. The cable length estimation circuit includes an edge rate detection circuit for measuring the rate of change in voltage with respect to time during transitions of the MLT-3 signal to provide an indication of cable length. The cable length estimation circuit can also include a digital averaging circuit which provides an average value for signals from the edge rate detection circuit for a desired number of transitions of the MLT-3 signal. The cable length estimation can also include a baseline wander detection circuit which functions so that previous cable length estimations are provided when baseline wander is detected.

摘要翻译： 一种电缆长度估计电路，用于接收通过任意长度的电缆提供的输入MLT-3信号，并向均衡器提供指示电缆的估计长度的控制信号，使得均衡器能够补偿来自所述MLT-3信号的失真 电缆。 电缆长度估计电路包括边缘速率检测电路，用于在MLT-3信号转变期间测量相对于时间的电压变化率，以提供电缆长度的指示。 电缆长度估计电路还可以包括数字平均电路，其为来自边缘速率检测电路的信号提供用于MLT-3信号的期望数量的转换的平均值。 电缆长度估计还可以包括基线漂移检测电路，其功能是使得当检测到基线漂移时提供先前的电缆长度估计。