Extraction of respiratory and cardiovascular signals from vibration sensitive mattress

It is shown that cardiovascular and respiratory activities can be detected using a single vibration sensor embedded in a mattress. A digital bandpass filter (BPF) has been constructed to process signals from the sensor to separate breathing and heartbeat related signals. In the time domain, short-time energy and pitch-wave signals are used to obtain the rates of cardiovascular and respiratory activities and identify sleep apnoea events