Accuracy and performance tests of a wireless georeferenced noise sensor for mobile noise sampling

Abstract

Wireless Sensor Networks (WSN) have been expanded due, among many other things, to the advances in technology and the cost reductions of electronic components, which allows to produce low-cost and low-power sensor nodes. With the aim of creating a WSN for automatic noise mapping, this paper evaluates the acoustical performance of an environmental noise sensor node for mobile sampling made-out of low-cost components. The sensor is composed of a low-power microcontroller together with a MEMS microphone, a Global Navigation Satellite System (GNSS) and a Low Power Wide Area (LPWA) wireless module. Acoustical tests were carried out to validate the sensor accuracy which could be compared to a Class 2 Sound Level Meter for Leq, LAeq and one-third octave band spectrum (63 Hz - 10 kHz). Moreover, signal processing, data management, low-power modes, among other tasks refinement, showed that the power consumption can be improved considerably