Session P32.9

Cardiac and Respiratory Monitoring through Non-Invasive and Contactless Radar Technique

M Varanini, PC Berardi, F Conforti, M Micalizzi,
D Neglia, A Macerata*

Università di Pisa
Pisa, Italy

The aim of this study was the evaluation of a microwave (MW) based device for vital signs monitoring of patients in hospital or home environment. The power of this approach stays not only in the novelty of the signals provided by the MW radar technique but in the extraction model mainly; the completely non-invasive method makes it valuable in situations that require monitoring of individuals at risk and for which it is impossible or not recommended the use of traditional instrumentation, both for their particular health conditions or non ideal healthcare conditions (at home), or simply to maintain a good quality of life (like the elderly or infants). The design and implementation of the radar instrumentation, the methods for signal processing and the obtained results have been compared with the theoretical analysis and modelling of the physical process and materials involved. Experimental tests were executed on volunteers in selected and controlled conditions and with different device setting: different radar frequencies, different distance of the device from the subject, with wall in between the device and subject; the subject was asked to do normal or deep breathing, or apnea. In each test session the MW signal was digitally acquired and saved together with true physiological signals coming from standard medical instrumentation. Single and multichannel data processing were applied in order to extract characteristic features from each signal and to identify any significant correlation. The analysis was applied both to the original signals and to the time series of derived parameters. The results of this study have highlighted the advantages and limits of this approach. Its main advantage is its ability to obtain precise indications on the movement of an individual in special and controlled conditions on small and specific physiological movements such as breathing or heartbeat, overcoming the skin and penetrating inside the human body. Nevertheless some limitations are clear, mainly related to the capacity to penetrate deeply into the body and to the poor spatial resolution.

(Abstract Control Number: 214)