The delay & sum algorithm applied to microphone array measurements: Numerical analysis and experimental validation

The experimental validation of the beamforming technique applied to microphone array measurements is investigated in this paper. At first the method theoretical background is presented, highlighting the main parameters affecting its performances and studying their influence with the aim of producing an instrument useful in designing an efficient experimental set-up. Then, in order to prove the theory assessment and to give a first estimation of the method uncertainty, an experimental campaign is carried out to validate the exposed theory under controlled and repeatable conditions. The obtained results highlight a very good correspondence between the theoretical model and the "in field" tests, giving the possibility to correctly design microphones array for future experimental campaigns. (c) 2007 Elsevier Ltd. All rights reserved.