公开(公告)号：AU2388400A

公开(公告)日：2001-07-09

申请号：AU2388400

申请日：1999-12-27

Applicant: TELOGY NETWORKS INC

Inventor： MLADENOVIC ZORAN ,  PATEL PIYUSH SHANKERBHAI

IPC: H04B3/23 ,  H04L5/14 ,  H04L25/49 ,  H04M1/60 ,  H04M11/00

Abstract: A modem-based echo cancellation enhancement for digital communications networks is provided. The effects on echo cancellation of non-linearity in a far end echo path in a digital telephone system are reduced by introduction of non-linearities into the near end signal prior to generation of the echo cancellation signal. Near end signal is sampled after linear to PCM conversion. A PCM to linear conversion is added prior to the echo canceler. The near end delay line can be provided between the converters to delay the signal as PCM samples, thereby reducing delay line memory requirements.

公开(公告)号：EP1157498A4

公开(公告)日：2002-04-17

申请号：EP99967632

申请日：1999-12-27

Applicant: TELOGY NETWORKS INC

Inventor： MLADENOVIC ZORAN ,  PATEL PIYUSH SHANKERBHAI

IPC: H04B3/23 ,  H04L5/14 ,  H04L25/49 ,  H04M1/60 ,  H04M11/00

CPC classification number: H04L5/14 ,  H04B3/23 ,  H04L25/4927

Abstract: A modem-based echo cancellation enhancement (10) for digital communications networks is provided. The effects on echo cancellation of non-linearity in a far end echo path in a digital telephone system are reduced by introduction of non-linearities into the near end signal prior to generation of the echo cancellation signal. Near-end signal is sampled after linear-to-PCM conversion (13). A PCM-to-linear conversion (25) is added prior to the echo canceler (14). The near-end delay line can be provided between the converters to delay the signal as PCM samples, thereby reducing delay line memory requirements.