The Environmental Noise Directive (END) requires that a five-year updating of noise maps is carried out, to check and report on changes that have occurred during the reference period. This led last year’s END to deploy several wireless acoustic sensor networks to improve evaluation of the impact of road traffic noise in the cities around the world. Nevertheless, the END opens the door to the analysis of sound taking into account its source. Annoyance is closely related to both the LAeq value (the equivalent value) of a sound and the type of sound (e.g., road traffic noise, music, birdsong, sirens, alarms, works...). Thus, a new generation of acoustic sensor networks should be designed, in order to come a step closer to sound mapping. So far, several noise mapping sensors, networks and platforms have been developed and deployed in some cities and suburban environments. This new approach is devoted to sound, and not just noise (which is usually limited to non-desired sounds). This new wireless acoustic sensor network requires broad knowledge in several disciplines: accurate hardware design for the acoustic sensors; artificial intelligence algorithms to differentiate the sources of noise; network structure design; information management, and graphical user interface design to communicate the results to users. This Special Issue focuses on all the technologies necessary for development of an efficient wireless acoustic sensor network, from the early design stages through to deployment testing, performance, and policy implications. This Special Issue, prepared by two guest editors, describes the latest trends in worldwide WASN design projects aimed at the design and implementation of smart acoustic sensor networks. The focus of the contributions is on good practice, suitable for the design and deployment of intelligent networks in other locations.
Dr. Rosa Ma Alsina-Pagès
Dr. Giovanni Zambon