Non-Invasive Heart and Respiratory Rates Extraction using Frequency-Modulated Continuous-Wave Radar

Abstract

Vital signs are often detected through contact-based techniques such as wrapping belt sensors around the patient's belly for monitoring respiratory rate and ECG for monitoring heart rate. Through the years, several off-body sensing techniques used in detecting heart and respiratory rates were developed. Non-invasive technology is the kind of technology that our society needs, especially when we suffer from viral diseases. This study aims to utilize the FMCW radar to extract the heart and respiratory rates. In the process of extracting the heart and respiratory rates, the subject would need to be in a controlled environment and 3.5 feet away from the device and 1.5 feet to the right for maximum accuracy. The device would need to be at the chest level of the subject while it is running. The corresponding heart and respiratory rates would then be displayed on a GUI. On the error threshold of the device compared to that of a commercial pulse oximeter, the radar module gained an MSE result of 0.74 for the heart rate and 1.64 for the respiratory rate. This indicates that the FMCW radar module measured relatively close values for heart and respiratory rates since the lower the MSE value, the higher the accuracy.