Design and Implementation of an Indoor Ambient Noise Monitoring System with Localization

Abstract

Inter-floor noise in apartment houses is a severe social problem that causes arson, violence, and even murder. This study proposes the design and implementation of an indoor ambient noise monitoring system to detect and record information related to indoor ambient noise in a building. The proposed system measures the noise level and estimates the source and direction of the noise. The noise level measurement is based on the sound pressure level (SPL) measurement, which is a logarithmic measure of the effective pressure of a sound relative to a reference sound pressure. Noise source localization was performed using the estimated time difference of arrival (TDOA) from the microphone array. In addition, a noise monitoring device was developed to deploy into the actual environment. The experimental results demonstrated that the proposed system had a reliable accuracy for each functional unit. The error of the noise level was approximately ±l.5dBA and the error of the direction estimation was approximately ±10 degrees. As a result, these output data from the proposed system are expected to be used as important reference data for any dispute cases due to indoor ambient noise. This study also describes a Smartphone connectivity via Bluetooth Low Energy.