An efficient maximum likelihood (ML) estimator to obtain the scatterin
g center locations of a target and the relative scattering level of th
ese scattering centers from the scattered field data is described, In
the proposed method, hit estimation is carried out in the image domain
rather than in the frequency-aspect domain, A two-dimensional (2-D) i
nverse Fourier transform is used to transfer the scattered field data
from frequency-aspect domain to the image domain (down-range/cross-ran
ge), As expected, the scattered field data in the image domain has som
e regions with high energy, The samples in the high-energy regions are
used to obtain the initial guess for the ML estimator as well as for
hit estimation, The ML estimator in the image domain is applied to bot
h simulated and experimental scattered fields of some targets.