Improved GPR image quality by truncating the bandwidth of the Fourier transform in 2D diffraction tomographic inversion

Diffraction tomography (DT) has been applied in ground penetrating radar (GPR) to obtain images of buried objects. In order to obtain a unique solution for the object function, a maximum frequency range should be used in a DT inversion routine. In this paper, a method is proposed to appropriately truncate the frequency range of the Fourier-transformed (FT) scattered field for a 2D DT inversion routine. This is achieved by determining the variation of the phase in the FT scattered field. The number of zero-crossings of the FT phase along the spatial axis is counted and a moving-average filter is applied to enable proper bandwidth selection. Numerical simulations are demonstrated using synthetic data with additive white Gaussian noise.