Article

On the ability of consumer electronics microphones for environmental noise monitoring

Ghent University, Department of Information Technology (INTEC), Gent, Belgium.
Journal of Environmental Monitoring (Impact Factor: 2.11). 12/2010; 13(3):544-52. DOI: 10.1039/c0em00532k
Source: PubMed

ABSTRACT The massive production of microphones for consumer electronics, and the shift from dedicated processing hardware to PC-based systems, opens the way to build affordable, extensive noise measurement networks. Applications include e.g. noise limit and urban soundscape monitoring, and validation of calculated noise maps. Microphones are the critical components of such a network. Therefore, in a first step, some basic characteristics of 8 microphones, distributed over a wide range of price classes, were measured in a standardized way in an anechoic chamber. In a next step, a thorough evaluation was made of the ability of these microphones to be used for environmental noise monitoring. This was done during a continuous, half-year lasting outdoor experiment, characterized by a wide variety of meteorological conditions. While some microphones failed during the course of this test, it was shown that it is possible to identify cheap microphones that highly correlate to the reference microphone during the full test period. When the deviations are expressed in total A-weighted (road traffic) noise levels, values of less than 1 dBA are obtained, in excess to the deviation amongst reference microphones themselves.

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    • "Additionally, 5 microphones were placed at the facades of some buildings of the network, at heights between 3 and 5 m, measuring continuously the L Aeq,1s evolution during the whole mobile measurements period. A detailed description of the noise measurement set up can be found in [27]. Two microphones were closely located near a crossing of the Doornzelestraat and the Sleepstraat, and one microphone was located in the middle of Sleepstraat; see their exact location in Fig. 2. Doornzelestraat and Sleepstraat are two busy 2-lane streets, with traffic flow rates that amount for light vehicles to about 4200 and 5800 Average Annual Daily Traffic for week days including holidays, respectively. "
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    • "framework of the IDEA project [10] was used. This large-scale measurement network consists of a series of low-cost intelligent measurement nodes equiped with a microphone [11]. "
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    • "More permanent monitoring would improve accuracy, but this was not feasible on this geographic scale at the start of the measurements in 1996. A possible approach is the use of low-cost microphones (from consumer electronics) which were shown to sufficiently accurate for typical environmental noise monitoring applications [6]. "
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