Effects of microphone position on snore signal quality and patient comfort

Studies on snore signal analysis have been widely conducted for detection of obstructive sleep apnea. Unfortunately, there is a lack of standardization and consensus in the signal acquisition techniques, hence weakening the diagnostic power of the studies. This paper therefore aims to explore the influence of microphone positioning on signal quality and patient comfort through objective and subjective measures, for example, sleep laboratory impulse response analysis, snore signal acquisition, and patient feedback survey. Results consistently show that the quality of snore signals, such as sound pressure level and signal-to-noise ratio, decreases above 10 dB when the mouth-to-microphone distance (MMD) changes from 0.1 m to 0.4 m, while the comfort level of patients rises with increasing MMD. Considering the trade-off between signal intelligibility and human comfort, we suggest keeping the microphone 0.3 m away from the patientpsilas mouth in order to achieve optimal signal quality with minimal patient discomfort.