@article {Yen:2023:0736-2935:2284, title = "Development of a continuous classroom signal-to-noise ratio measurement system", journal = "INTER-NOISE and NOISE-CON Congress and Conference Proceedings", parent_itemid = "infobike://ince/incecp", publishercode ="ince", year = "2023", volume = "268", number = "6", publication date ="2023-11-30T00:00:00", pages = "2284-2291", itemtype = "ARTICLE", issn = "0736-2935", url = "https://ince.publisher.ingentaconnect.com/content/ince/incecp/2023/00000268/00000006/art00032", doi = "doi:10.3397/IN_2023_0337", author = "Yen, Benjamin and Hui, C. T. Justine and Bergin, Esther and Jensen, Eleesa and Purdy, Suzanne C. and Keith, William and Hioka, Yusuke and Whitlock, James and Dodd, George", abstract = "A successful learning experience requires children to be able to hear what the teacher is saying. To that end, children need a high signal-to-noise ratio (SNR) or speech audibility to hear the teacher under background noise, but SNR in the classrooms may not always be favourable depending on the activities taking place during a school day. We propose a classroom acoustic measurement system to monitor the time-varying SNR under interactive teaching scenarios. Emulating a child listening to the speech made by a teacher, the system utilises two consumer-grade wireless microphones, one attached to the teacher and the other located where the children would be seated. The signal received by the teacher's microphone is used as a voice activity detector to indicate the presence of the teacher's voice or noise-only audio instances. Subsequently, the children's microphone observes these instances to monitor the average classroom noise and estimate the resulting SNR. A pilot study was conducted at a primary school in Auckland, New Zealand where the SNR measurements were recorded and matched against behavioural coding of the classroom activities. Results show a reasonable agreement of the SNR to the activities performed under real-life classroom teaching scenarios.", }