Validation of a contactless radar system for continuous respiratory rate and heart rate monitoring in clinical and simulated use conditions

Abstract Continuous monitoring of respiratory rate (RR) and heart rate (HR) remains limited in post-acute and long-term care (PALTC) settings, where intermittent spot checks may delay detection of clinical deterioration. Contactless radar-based sensing offers an unobtrusive alternative suited to these environments. This study validates the performance of the C300 Monitor, a contactless frequency-modulated continuous-wave (FMCW) radar system operating at 58.0–61.5 GHz, for continuous RR and HR monitoring across clinical and simulated use conditions. In a clinical validation study conducted in such PALTC facilities, C300-derived RR and HR were compared against carbon dioxide capnography and electrocardiography, yielding Bland-Altman limits of agreement of -1.9 to 2.7 breaths per minute for RR, and -2.9 to 2.5 beats per minute for HR, with accuracy rates of 99.8% for RR and 95.1% for HR within a ±5 breaths per minute and beats per minute error margin, respectively. A complementary laboratory study evaluated system performance across representative conditions, including varying device distances, body positions, and motion scenarios. Under motion-free conditions, accuracy rates exceeded 96.3% for RR and 90.6% for HR within the same error margin, while expected system behavior was observed during patient motion or absence. Across both studies, the C300 Monitor demonstrated reliable, continuous RR and HR monitoring under conditions representative of real-world care environments, supporting its suitability for unobtrusive vital sign monitoring in these settings.