The layered media inverse Q filtering algorithm for GPR signals processing based on wavefield downward continuation

Layered medium attenuation algorithm using constant Q model for ground penetrating radar (GPR) signals processing is introduced in the paper. We can use different Q value to describe different layered media. And an inverse Q filtering for GPR signals, based on the theory of wavefield downward continuation is presented. This filtering is tested in a layered-earth Q model where the Q is assumed a depth dependent one. For each individual constant Q layer, the GPR wavefield recorded at the surface is first extrapolated down to the top of the current layer and a constant Q inverse filter is then applied to the current layer. Within the current constant Q layer and the wavefield is resampled in the frequency domain. The amplitude compensation operator, which is a 2-D function of travel time and frequency, is approximated optimally as the product of two 1-D functions depending, respectively, on time and frequency. The algorithm is tested and the result shows that the amplitude attenuation of GPR has been compensated, and the wavelet dispersion is removed to some extents.