Identification of Sources of Uncertainties in CW Microwave Noncontact Vital Sign Measurement

Continuous Wave (CW) microwave radars have attracted the interest from the research community for contactless, low-power and non-ionizing detection of human respiratory and heart frequencies. Optimum radar architecture design and optimization require the identification of systematic and non-systematic errors in both guided and radiating microwave paths of the system. In this effort, an heterodyne CW radar built up with reference measurement instrument is used to accurately identify sources of errors. The measurement campaign is very instructive, providing a guide to improve CW radar architectures implementation.