Detection and analysis of human motion by radar

Human motion has complex articulation and flexibility and, thus, is a non-rigid body motion. Radar returns from human with motions are subject to Doppler modulations that provide information about motion dynamics. In this paper, we first discuss radar backscattering from a walking human model and based on the model we derive motion trajectories and velocity patterns of human body parts. Then, we discuss how to analyze the radar backscattering from a subject of interest and how to use time-frequency transform to analyze micro-Doppler signatures of human movements. Finally, we introduce an example of the radar backscattering from human complex arm and leg motions. We characterize and explain micro-Doppler signature of the complex arm and leg motions.