Numerical simulation of UWB impulse radar vital sign detection at an earthquake disaster site

Using the finite difference time domain (FDTD) numerical simulation approach and synthetic computational experiments we investigated the use of the ultra-wide band (UWB) radar technique for human vital sign detection under collapsed building debris caused by catastrophic earthquakes. The model of the collapsed building was developed based on a real situation from an earthquake disaster site. The model consists of two human beings with different characteristics of vital signs, i.e., with different cardio-respiration features, posed in different positions, and buried at different depths in the debris. Analysis of the synthetic data indicates that the UWB impulse radar can identify and separate the human subjects’ vital sign for a radar record as short as 20 s. The simulation approach was verified with a physical experiment using impulse UWB radar with two human subjects positioned behind a concrete wall. Advanced signal processing of source separation and signal processing using empirical mode decomposition were conducted to identify and locate the human subjects. The results show that this approach is a promising technique for search and rescue of living victims at disaster sites.