Sound source identification using coherence and intensity based methods

Very often in environmental and industrial acoustics it is necessary to identify the contribution of single sources to global levels. Under this perspective usually interests arise from the necessity of controlling noise or verifying whether a single source exceeds legal limits, although there are other active sources around. Currently available methods are typically based on coherence or expert systems techniques. Both approaches have relevant limitations, but, for current purposes, coherence methods are usually more robust, especially if carried out using vibration sensors in vibro-acoustic interactions. Nevertheless when a measurement system is based only on microphone measurements also those methods have too little reliability and unsatisfying accuracy, since it´s quite impossible to eliminate in input signals the effects of other sources, which usually have some coherence also with output signal. In this paper a relevant enhancement to coherence-based methods, obtained by means of an acoustic-intensity measurement approach, is presented.