Wearable system for measurement of thoracic sounds with a microphone array

Acoustic signals from the thorax provide diagnostic information about the heart, the respiratory and the digestive system. This information is useful for both the detection of acute illness, e.g. in elderly care, and for the monitoring of chronic diseases. Here, a wearable system for long-term capture of thoracic sounds is proposed that comprises four microphones for physiological signals and one for noise from the surrounding. The performance of the prototype is evaluated in comparison to a reference stethoscope and under different wearing conditions. Combining the microphones will provide means for cancellation of environmental noise, fusion of acoustic signals from different physiological sources as well as focusing on a particular source by use of beamforming.