MUHD: A multi-channel ultrasound prototype for remote heartbeat detection

This paper presents a novel system based on ultrasonic waves that is capable of detecting heartbeat in a contactless fashion. The aim of this work is to design, build and test a prototype that could be effective, simple in its realisation and use and with a low cost of production. The idea is the exploit the displacement of the skin related to cardiac activity, that is possible by using phase difference between a transmitted wave and the waves resulting from the interaction with the subject skin. Nevertheless, this type of procedure is not new in the scientific literature, but in this manuscript the authors contribution mainly consists in the implementation of a multi-channel architecture in order to overcome the well known “null-point” issue. Furthermore, an a-priori regularisation function is used for making the system more robust against noise and artifact. The performance of the prototype has been tested on volunteers and the results are quite close to standard electrocardiography used as reference.