Noncontact multiple targets vital sign detection based on VMD algorithm

In recent years, biomedical radar technology has attracted great interest in various fields. Comparing with single target scenario, multiple vital sign detection is a more challenging task. In this paper, a novel noncontact multiple targets vital sign detection method using ultra-wideband (UWB) radar system has been proposed. Utilizing Variational Mode Decomposition (VMD) algorithm, the respiration signals of different targets can be decomposed into different sub-signals when multiple targets located at the same distance. Therefore, time-varying respiration rates can be tracked accurately via Hilbert transform. Various experiments have demonstrated that vital sign of two targets, even up to four targets can be detected and distinguished clearly, which exhibit the effectiveness and robustness of the proposed method in indoor application.