Implementation and analysis of respiration-rate estimation using impulse-based UWB

Previous work has shown that UWB systems can be used for remote vital-signs monitoring, with the major applications of these systems being in health monitoring and rescue scenarios. In this paper, we demonstrate the use of impulse-based UWB signals in the robust detection of chest-cavity motion and the accurate estimation of respiration and heart-beat rates, even in the presence of physical obstructions between the subject and the UWB antennas. The main contribution of this paper is an analytical framework for the development of signal processing algorithms to estimate respiration and heart rates and corroboration of the techniques with measurements. The analogy between the bandwidth of narrowband phase-modulated (PM) systems and the estimation problem is recognized through this analysis and is used to determine optimal parameters such as pulse width and sampling frequency for future experiments. We also present the results of several real-time experiments conducted under different scenarios to demonstrate the accuracy of our techniques in determining respiration and heart-rates.