Multi-Microphone Signal Processing for Acoustic Echo Control

Acoustic echoes are one of the most annoying disturbances in hands-free telephony. Usually, they are suppressed by acoustic echo cancellers accompanied with additional post-processing. Besides that, acoustic interferences and reverberation of the desired speech signal disturb effortless speech communication. Recent and advanced hands-free devices employ - among other techniques - microphone arrays to overcome these two latter problems. The present work investigates opportunities to enhance acoustic echo suppression by means of spatial cues, which become available with microphones arrays. This includes two fields: the actual suppression of echo components in the microphone signal and the adaptation control of the acoustic echo canceller.