UWB-TWDR, Detection And Location Moving Target

There are numerous occasions which need to inspect the interior of a room, a building or a blindage when physically entering the room is impossible or hazardous, such as urban-warfare, counter-terrorism, civil engineering and law-enforcement scenarios. The Ultra-Wideband Through-Wall Detecting Radar (UWB-TWDR) is a kind of candidates which can finish these tasks well.This thesis analyzes the propagation property of the electromagnetic wave through non-metallic materials and walls. The formula of propagation attenuation is deduced when the wall is supposed as a parallel-plate media. Then, the method of conducting surveillance through walls with a low frequency radar is discussed. The parameters of radar are selected and a prototype of UWB-TWDR which can detect, locate and track the moving persons behind the partitions is designed and realized. The models of moving target are given for UWB-TWDR. The refracting offset is calculated quantitatively in this thesis. The principle of moving target detection is provided with coherent superimposing technique on the moving target models. Based on the technique of trilateration, a moving target can be positioned with one transmitter and two receivers, and the modified trilateration technique that can locate the target with two circles is discussed for the prototype of UWB-TWDR.The frequency range of UWB-TWDR includes RF band occupied by FM radio, TV and some communication systems. As a result, radio frequency interference (RFI) appears in its received signal and the random RFI obscures the target in the scene. The random RFI that received by UWB-TWDR are suppressed by the algorithms of principle of mean square error (MSF,) and spatially selective filtration in wavelet domain.Finally, the performance of the UWB-TWDR is validated by the experiments for penetrating a wood block door, an ordinary concrete wall and a reinforced concrete wall.