Distributed intelligent sound processing system

Source localization of objects using sound waves and vibrations is very important for many applications that range from military to security and home automation systems. Typical applications include tracking a moving object in security systems, where the location of a sound is needed to direct a camera, or selecting the closest microphone to a speaker from a microphone array, as in the case of a voice automated home. The simpler cases of sound localization, as in the last example, are the focus of the project we present in this paper. The system described in the paper is designed around a master module for control and multiple intelligent sound processing modules (ISPM) with omnidirectional microphones, signal conditioning and digital signal processing. All modules are connected using a differential serial bus using a custom time division multiplexing (TDM) master/slave protocol. In this paper we describe the protocol, the theory of operation, and first experiences with the prototype system.