  Imaging for an occluded object is usually a difficult problem, in this
letter, we introduce an imaging scheme based on computational ghost imaging,
which can obtain the image of a target object behind an obstacle. According to
our theoretical analysis, once the distance between the object and the obstacle
is far enough, one can obtain the image of the object by using ghost imaging
technique. The wavelength of the light source also affects the quality of the
reconstructed image. In addition, if the bucket detector is placed far away
from the obstacle, a tiny point-like detector without collecting lens can be
applied to realize the imaging. These theoretical results above have been
verified with our numerical simulations. Furthermore, the robustness of this
imaging scheme is also investigated.
