公开(公告)号：US20070223407A1

公开(公告)日：2007-09-27

申请号：US11386366

申请日：2006-03-22

Applicant: Terry Engel

Inventor： Terry Engel

IPC: H04B3/20

CPC classification number: H04B3/23 ,  H04M3/002 ,  H04M2201/52

Abstract: A method and system for far echo rejection for a fax modem control channel is disclosed for eliminating far echo signals during a fax transmission with a fax modem using a control channel and a primary channel for transmitting data. The far echo rejection may be achieved even if the fax modem standard utilized does not include far echo training. An echo detection control frame is transmitted during the initial fax transmission control channel communications. Far echo rejection can be achieved by monitoring for an echo of the sent echo detection control frame, measuring the detected echo level, recording the echo level, and rejecting signals below a threshold based upon the echo level. Signals at or above the echo threshold level are treated as fax signals while signals below the threshold level are assumed to be far echoes.

Abstract translation: 公开了用于传真调制解调器控制信道的远回波抑制的方法和系统，用于在使用控制信道的传真调制解调器和用于发送数据的主信道的传真传输期间消除远端回波信号。 即使所使用的传真调制解调器标准不包括远回波训练，也可以实现远端回波抑制。 在初始传真传输控制信道通信期间发送回波检测控制帧。 通过监测发送的回波检测控制帧的回波，测量检测到的回波电平，记录回波电平以及基于回波电平将信号抑制在阈值以下，可以实现远端回波抑制。 回波阈值以上的信号被视为传真信号，而低于阈值电平的信号被认为是远响应。