Extending the scope of unattended environmental noise monitoring
- Resource Type
- Electronic Thesis or Dissertation
- Authors
- Wright, Philip
- Source
- Subject
- 620.23
Road traffic
Aircraft
Railway
- Language
- English
UK planning and noise regulations are source-specific, implying that individual noise source contributions need to be measured separately. The only way of doing this in many situations is through attended measurements, which makes monitoring at many positions and the fulfilment of measurement sampling requirements an often lengthy and labour-intensive exercise. Calculation procedures are often used as an alternative to measurement but these only provide an estimate of the actual noise climate. These factors make unattended measurement of environmental noise with a system that can automatically identify contributing sources an attractive proposition. Whereas existing techniques for unattended source-identifying measurement are concerned mainly with specific permanent monitoring problems (most usually around airports) this study is concerned with the development of a generally applicable system for measurement of transportation noise sources; one that seeks to extend the possibilities for unattended monitoring to the greatest possible range of sites and in the simplest possible manner. Existing permanent monitoring systems generally operate through detection of a specific set of acoustic features present at one particular site. However, such is the variability and overlap in the nature of the noise from generic source categories as one moves from site to site that such an approach is inappropriate and impractical for the general case. The locational separation of sources has been identified as the key to the development of a workable automatic system, and it has been shown that utilisation of this spatial information through widely-spaced microphones leads to a comparatively simple method for unattended measurement. A 'reference' microphone is responsible for measurement of the total noise at the prescribed measurement position whilst other 'remote' microphones are deployed around the site in such a way as to ensure a different response to each source.