An experimental study: Detecting the respiration rates of multiple stationary human targets by stepped frequency continuous wave radar

In this study, it is aimed to improve the maximum range and range resolution while detecting multiple targets’ respiration rates. An original algorithm has been proposed for this purpose, and a Stepped Frequency Continuous Wave radar has been set up for experiments. Experiments have been executed with periodically moving plates and human targets. With a resolution of 30 cm, the detected maximum ranges are 7 m and 6.3 m for moving plate and human targets, respectively. In moving plate experiments, the average accuracies of the frequency measurements are above 98% for both single and multiple-target scenarios. In human target experiments, the average accuracy of the respiration rate measurements is 96.58% for single target experiments while it is 94.44% for multiple targets. The results show that the proposed structure outperforms the state-of-the-art benchmark in terms of the capability of sensing the respiration rate in a wide range with a high resolution.