Microphone Array Front-End Interface for Home Automation

In this paper we present a microphone array (MA) interface to a Spoken Dialog System. Our goal is to create a hands- free home automation system with a vocal interface to control home devices. The user establishes a dialog with a virtual butler that is able to control a plethora of home devices, such as ceiling lights, air-conditioner, windows shades, hi-fi and TV features. A MA is used for the speech acquisition front-end. The multi-channel audio acquisition is pre-processed in real-time, performing speech enhancement with Delay-and-Sum Beamforming algorithm. The Direction of Arrival is estimated with the Generalized Cross Correlation with Phase Transform algorithm, enabling us to track the user. The enhanced speech signal is then processed in order to recognize orally issued commands that will control the house appliances. This paper describes the complete system emphasizing the MA and its implications on command recognition performance.