Design of Low-Cost Noise Measurement Sensor Network: Sensor Function Design

In this paper, we report the sensor function design and implementation of a wireless sensor network application for measuring environmental acoustic noise. The system is built on ATmega128 and CC2420 platform. The protocol stack is based on CiNet stack with a global synchronization scheme and supports multi-hop communications. Strict filtering function specified by ITU-R 468 (namely A-weighting) is followed. Both the indoor and outdoor test results were compared with standard sound level meters (CESVA SC-20c and Pulsar94) and showed a less than ±2dB error in both short-term and longterm measurement. Power consumption has been measured that a single AA-type battery can sustain the application. Comparing to the traditional noise measurement method, our wireless sensor network solution is much lower in cost, able to offer real-time data with sensed data timely coherent, and requests least attention after deployment.