Space-frequency sampling criteria for electromagnetic scattering of a finite object

The sampling criteria in the wavenumber space for generating the spatial impulse response of a finite target is described. A proper choice of canonical confinement for the target in space can greatly reduce the number of samples required to sufficiently characterize the target´s spatial impulse response. Though a sampling lattice may be more efficient in the sense of a reduced number of measurement points per unit volume of hyperspace, it may be less effective when digital processing is involved. Specifically, the time-consuming interpolating step is required to put data presented in other types of sampling lattice into the proper type for the computer. Two-dimensional impulse responses reconstructed from cubic sampled data are compared with those using Mensa et al.´s method. The responses obtained also indicate good potential for image reconstruction via the spatial impulse response.