Analysis of the measurement uncertainty and its effects on noise mapping validations

This paper addresses the use of noise measurements when noise mapping simulations are intended to be validated. For this, a discussion about the measurement uncertainty and how to include it in the process of validation is carried out. Then, the contribution provided by the geo-referencing error of a GPS and its impact in the uncertainty is assessed. This is achieved by means of environmental noise measurements, which are conducted based on the accuracy radius given by a standard GPS. Furthermore, an assessment of the approach is conducted by means of numerical simulations using the commercial package SoundPLAN. The results indicate that the uncertainty of noise measurements should be included as it restricts the validation threshold (usually assumed as +/- 3 dB). Furthermore, the error generated by the inaccuracy of the geo-referencing process increases the uncertainty of the measurements and, therefore, of the noise maps. Finally, a method to calculate a total uncertainty, which partially includes the contributions of the geo-referencing error is also proposed.