Our implementation of a G.167 compliant Acoustic Echo Canceller is designed to cancel acoustic feedback between a loudspeaker and a microphone in loudspeaking audio systems. The tail length of the echo suppression can be adjusted to system requirements. The algorithm is required in speaker phones, teleconferencing devices, voice-control systems or alike. This AEC requires very few MIPS making it suitable even for micro-controller platforms.

• Software controlled Coefficient Adaptation
• Software controlled Leakage
• Software controlled Non-linear Processor (NLP)
• Software controlled Howling Control
• Double Talk Detector with Adaptation Control
• Programmable Tail Length
• Field proven technology
• Low MIPS per channel

Specifications

• 10 MIPS per channel (32 msec tail)
• < 2K words program memory
• max. 250 msec tail @ ~50 MIPS
• 80 + 32*T bytes data memory (T = tail in msec)
• Single Talk Attenuation > 45db
• Double Talk Attenuation > 30db
• Convergence ~ 20dB/sec
• ITU G.167 compliant

Platforms

The algorithm is available for Analog Devices Blackfin and Texas Instruments TMS320C54x/C55x. The API for all platforms is designed to be independent of signal source and sink. The code is fully re-entrant allowing multi-channel applications to be easily realized.
We have demo code available for standard evaluation platform, e.g. C55 DSK or Blackfin EZKit which we can provide to our (potential) customer on short notice. If required, we can port the existing code to other platforms - all you need to do is ask.

Datasheets

G.167 AEC for Analog Devices Blackfin
G.167 AEC for Texas Instruments C5000
G.167 AEC for Texas Instruments C6000

If you wish to learn more about our line echo cancellers, please contact us.