Estimation of Noise Immission Directivity using Small Microphone Array
Proceedings of the ICA congress
Ever increasing processing power enables the development of advanced equipment for environmental noise measurements, capable of complex processing of multichannel signals. Consequently a research has been undertaken to develop a handheld size beamforming system for two new measurement options: 1) immission directivity, 2) noise source classification, based on the immission directivity. In this paper a new physical property, called immission directivity, is defined in a way which enables
... ich enables traceability to SI units. Furthermore, the immission directivity and temporal direction of noise immission can be used as features for classification of noise sources arranged around the immission point. As such it can be used in real time for triggering of equivalent noise level integration. Statistical analysis shows, that it enables measuring of more random environmental noise sources and calculating their contribution to the overall noise level. Three case studies have been performed using proposed measuring options. Two new options revealed significant advantages over classical noise monitoring systems by improving the validity and the presentation capability of results. Implementation of these two options into noise monitoring equipment reduces human resources, resulting in reduced measurement costs, and provides more accurate results. Additional advantage of the new measurement options is their ability to provide information which is necessary for design of noise control measures.