Acoustic echo control and noise reduction for cabin car communication

Abstract

A Cabin Car Communication System (CCCS) has the goal of improving the communication among passengers inside the car. Wind, road and engine noise, the distance between passengers and other factors make difficult the communication inside vehicles. The driver must often look away from the road and passengers move out of normal seating positions. The CCCS makes use of a set of microphones to pick up the speech and the car-audio loudspeakers to reinforce the sound level. This scenario presents a great challenger for acoustic echo control and noise reduction. Acoustic echo control must prevent the overall system from howling and becoming unstable with the additional problem that the system must always work with double talk. The noise reduction must clean the microphone signal to avoid the reinforce of the noise inside the car. In this paper, we describe a combined acoustic echo control and noise reduction algorithm suitable for cabin car communication systems. We present experimental results in terms of echo return loss enhancement, stability and maximum reinforce without howling.