Research On Non - Contact Multi - Target Life Signs Detection Algorithm Based On UWB Radar

Based on the ultra-wide-band (UWB) radar, the non-contact multiple targets vital sign detection system combines the biomedical technology and modern radar technology. It aims at acquiring the vital sign information, which includes breathing, heartbeat and so on, from single or multiple targets in real time wirelessly. This technology has a broad application prospect. It not only has a huge potential market in family health, but also can be used to earthquake search and rescue. Meanwhile, it also has a good prospect in the hospital patient care.In this thesis, the signal processing algorithm for UWB radar multiple targets vital sign detection has been studied. First, the disadvantages and the insufficiencies of the Empirical Mode Decomposition (EMD) algorithm has been analyzed. Then focus on these problems, the Variational Mode Decomposition (VMD) algorithm is proposed to process the signal. Two sets of experiments (single target and multiple targets experiments) has been set up to acquire the vital sign signals, and both EMD and VMD algorithms have been applied to the separate the vital sign signals, respectively. After simulation and the measured signal test, it is found that the EMD algorithm has great limitations in vital sign signals separation. However, the VMD algorithm overcomes the shortcomings existing in the EMD algorithm with good robustness. It has a good effect in separating the vital sign signals with different frequencies.The VMD algorithm is also programmed on the TMS320C6678-based DSP platform. The simulation and debugging have been conducted to realize the separation of signals with different frequencies successfully on the DSP. The results show that the VMD algorithm in multi targets vital sign detection is feasible.