Laboratory UWB GPR system for landmine detection

In this paper, the design and the modelling of an indoor impulse UWB GPR systems (1GHz-5GHz), built in the scope of the HUDEM project, is presented. For an impulse UWB system, a time-domain modelling is an obvious choice. We explain how the antennas can be characterised by their normalised impulse response. By considering the antenna as a convolution operator, we get a mechanism for modelling the whole radar system as a cascade of linear responses, which gives a lot of advantages and possible application. In our research it is used to express the radar range equation in the time-domain, to optimise the antenna configuration and to tune signal-processing algorithms. The deconvolution of the signal source and antenna impulse responses is an ill posed operation. In this paper we present method for decomposing an A-scan in a linear combination of wavelets, using the Continuous Wavelet Transformations - by properly choosing the mother wavelet. This technique can also be used to reduce the amount of data for further processing. Finally, results obtained by our UWB GPR system are shown. Advantages and shortcomings are discussed.