DIGITAL SPEECH offers  Line echo cancellers  for VoIP and VoP gateways. DIGITAL SPEECH offers two types of gateways line echo cancellers : Standard and Enhancement. Both cancellers are intended for near and far echo suppression. The Standard LEC is intended for work in multi-channels gateways connected to classic telephone network without VoIP segments. The Enhancement LEC is intended for work in modern telephone networks with VoIP segments

The Standard gateways LEC is intended for work in multi-channels gateways connected to classic telephone network without VoIP segments. This algorithm has extremely  low CPU load and allows to build gateway with very high channel density. It can suppress far and near echo and corresponds to ITU-T G.168-2004 requirements. The following figure shows telephone network structure where such line echo canceller can be used.

• Fast convergence
• Fast reconvergence after echo path change
• Maximal echo path up to 128ms
• Extremely low CPU load which is independent from maximal echo path
• Robust double talk detector
• Non-linear processor
• Comfort noise generator matched with original noise
• Internal tone detector preventing convergence to local minimum
• Meets G168-2004 requirements

The Enhanced gateways LEC is intended for work in multi-channels gateways connected to modern telephone network with VoIP segments. It has very long maximal echo path (up to 256ms), protection against to non-linear distortions and background noise, the special features for fast reconvergence after echo path change, low CPU load which is independent from maximal echo path.  Also this canceller can be used for acoustic echo suppression in mobile phones. It can suppress far and near echo and corresponds to ITU-T G.168-2004 requirements. The following figure shows telephone network architecture where such line echo canceller can be used.

• Fast convergence
• Fast reconvergence after echo path change
• Robustness in respect to background noise and non-linear distortion
• Maximal echo path up to 256ms
• Low CPU load which is independent from maximal echo path
• Robust double talk detector
• Non-linear processor
• Comfort noise generator matched with original noise
• Internal tone detector preventing convergence to local minimum
• Noise suppressor
• Meets G168-2004 requirements
• Reliable work in networks with VoIP segments