A wearable, mobile phone-based respiration monitoring system for sleep apnea syndrome detection

Biomed Sci Instrum. 2005;41:289-93.


A new wearable respiration monitoring system has been developed for non-invasive detection of sleep apnea syndrome. The system, which is attached to a shirt, consists of a piezoelectric sensor, a low-power 8-bit single chip microcontroller, EEPROM and a 2.4 GHz low-power transmitting mobile phone (PHS). The piezoelectric sensor, whose electrical polarization voltage is produced by body movements, is installed inside the shirt and closely contacts the patient's chest. The low frequency components of body movements recorded by the sensor are mainly generated by respiration. The microcontroller sequentially stores the movement signal to the EEPROM for 5 minutes and detects, by time-frequency analysis, whether the patient has breathed during that time. When the patient is apneic for 10 sseconds, the microcontroller sends the recorded respiration waveform during and one minute before and after the apnea directly to the hospital server computer via the mobile phone. The server computer then creates apnea "filings" automatically for every patient. The system can be used at home and be self-applied by patients. Moreover, the system does not require any extra equipment such as a personal computer, PDA, or Internet connection.

Publication types

  • Evaluation Study

MeSH terms

  • Cell Phone / instrumentation*
  • Diagnosis, Computer-Assisted / instrumentation*
  • Diagnosis, Computer-Assisted / methods
  • Equipment Design
  • Equipment Failure Analysis
  • Humans
  • Monitoring, Ambulatory / instrumentation*
  • Monitoring, Ambulatory / methods
  • Polysomnography / instrumentation*
  • Polysomnography / methods
  • Respiratory Mechanics*
  • Sleep Apnea Syndromes / diagnosis*
  • Telemedicine / instrumentation*
  • Telemedicine / methods
  • Telemetry / instrumentation
  • Telemetry / methods
  • Transducers