This study aimed to produce a prototype system for non-contact vital sign monitoring of the elderly using microwave radar with the intention of reducing the burdens on monitored individuals and nursing care-givers. In addition, we tested the ability of the pro-posed prototype system to measure the respiratory and heart rates of the elderly in a nursing home and discussed the systems effectiveness and problems by examining results of real-time monitoring. The proto-type system consisted of two 24-GHz microwave ra-dar antennas and an analysis system. The antennas were positioned below a mattress to monitor motion on the body surface for measuring cardiac and respi-ratory rates from the dorsal side of the subjects (23.3 ± 1.2 years) who would be lying on the mattress. The heart rates determined by the prototype system cor-related significantly with those measured by electro-cardiography (r = 0.92). Similarly, the respiratory rates determined by the prototype correlated with those obtained from respiration curves (r = 0.94). Next, we investigated the effectiveness of the proto-type system with 7 elderly patients (93.3 ± 10.56 years) at a nursing home. The proposed system appears to be a promising tool for monitoring the vital signs of the elderly in a way that alleviates the need to attach electrodes overnight to confirm patient safety.
Suzuki, S., Matsui, T., Kagawa, M., Asao, T., & Kotani, K. (2013). An approach to a non-contact vital sign monitoring using dual-frequency microwave radars for elderly care. Journal of Biomedical Science and Engineering, 06(07), 704–711. https://doi.org/10.4236/jbise.2013.67086