 Smoothing window will help us smoothen the estimate.Wider the main lobe of the smoothing spectrum, smoother it becomes at the cost of frequency resolution.For further details on spectral estimation, please refer Spectral Analysis of Multi-dimensional signals

The method being discussed here assumes that the mass distribution of the underground objects of interest is already known and hence the problem of estimating their location boils down to parametric localisation.Say underground objects with center of masses (CM1, CM2...CMn) are located under the surface and at positions p1, p2...pn.