Sleep apnea syndrome is a prevalent chronic condition that disrupts daily functioning. As its incidence rises, there is a clear demand for an affordable, portable device capable of detecting apneic events and monitoring heart rate. This study followed a three-stage process of design, simulation and implementation, and benchmarked heart-rate data against those obtained from a Ticwatch 3 Pro. Two heart-rate monitor prototypes and one respiration monitor were developed. The first heart-rate prototype employed a low-pass filter with a wrist-mounted piezoelectric sensor. The second prototype used a band-pass filter with the sensor positioned on the tester’s back, shared with the respiration monitor. Linear regression and correlation analyses demonstrated that the low-pass filtered wrist-mounted configuration yielded more reliable measurements than the band-pass filtered design.

Yueming Wen. Apnoea Monitor Using a Piezo Sensor and Filters. Frontiers in Medical Science Research (2025), Vol. 7, Issue 4: 30-39. https://doi.org/10.25236/FMSR.2025.070404.

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