[3] [3] PEVERNAGIE D,AARTS R M,MEYER M.The acoustics of snoring［J］.Sleep Medicine Reviews,2010,14(2):131-144.

[4] [4] ERDENEBAYAR U,PARK J U,JEONG P,et al.Obstructive sleep apnea screening using a piezoelectric sensor［J］.J Korean Med Sci,2017,32(6):893-899.

[5] [5] TUNCER A T,BLGEN M.A viable snore detection system:hardware and software implementations［J］.Turkish Journal of Electrical Engineering & Computer Sciences,2020,28(2):1059-1069.

[6] [6] XIN Y,LIU T,LIU H,et al.A bone-conduction transducer-based detection system for sleep apnea screening in the family units［J］.IEEE Sensors Journal,2021,21(6):8411-8420.

[7] [7] NG,ZHI J H,TONG S K.Effects of microphone position on snore signal quality and patient comfort［C］//［S.l.］:IEEE International Conference on Signal Processing,2008:2130-2133.

[8] [8] XIN Y,LIU T,SUN H,et al.Recent progress on the wearable devices based on piezoelectric sensors［J］.Ferroelectrics,2018,531(1):102-113.