Consider the inverse acoustic scattering of time-harmonic point sources by an
unbounded locally rough interface with bounded obstacles embedded in the lower
half-space. A novel version of reverse time migration is proposed to
reconstruct both the locally rough interface and the embedded obstacle. By a
modified Helmholtz-Kirchhoff identity associated with a planar interface, we
obtain a modified imaging functional which has been shown that it always peaks
on the local perturbation of the interface and on the embedded obstacle.
Numerical examples are presented to demonstrate the effectiveness of the
method.Comment: 21 pages, 19 figure