Applications to Real Measured Data - Introduction to Imaging from Scattered Fields - page 126

Ref

Causal V Ψ

(a) (b)

3

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(c) (d)

Filter

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Figure 9.11 Homomorphic filtering applied to FoamDielInt at 6 GHz: (a) Causal k -space data with reference
point, (b) minimum phase V Ψ , (c) log-plot of cepstral domain, (d) Gaussian filter, and (e) cepstral reconstruction.

that | kVa | ≪ 1. In addition, Figure 9.14b illustrates that for high frequencies
the k -space coverage available from the measured data is insufficient to avoid
strong side lobes, which can appear as replicas of the central lobe.
This means that for a reconstruction based on the Born approximation one
would expect an optimum performance at some lower frequencies, perhaps
including more measured data at a larger number of incident and scattering