| Ultra-wideband radars are used for several applications such as subsurface sensing, classification of aircrafts and collision avoidance. The detection of humans hidden by walls or rubble, trapped in buildings on fire or avalanche victims are of interest for rescue, surveillance and security operations. Ultra-wideband technology is favored for these applications due to its inherent property of ultra-high resolution and the ability to penetrate most of the non-metallic building materials such as bricks, wood, dry walls, concrete and reinforced concrete.;Detection of human beings with radars is based on movement detection---respiratory motions and movement of body parts. These motions cause changes in frequency, phase, amplitude and periodic differences in time-of-arrival of scattered pulses from the target, which are result of periodic movements of the chest area of the target. In this thesis, the emphasis is on detection techniques for a stationary human target behind the wall for different types of walls using monostatic Ultra-wideband radar. For respiratory motion detection, the techniques employed were Normalized Square of difference of successive scans method, Reference moving average method, Discrete Fourier transform method and Empirical mode decomposition from Hilbert-Huang transform method. The experimental results for human target detection behind the wall have been demonstrated. |
