  Anisotropic acoustic metamaterials have been proved very useful for their
high potential in guiding and manipulating sound energy. In this paper, we
further develop the idea by using periodically layered structures for
transformational acoustics. Such a simple scheme periodically inserts
identically bent solid plates in a background fluid. It forms a metamaterial
with high refractive index normal to the curved plates and an index near to one
along the plates. We show that the periodically layered structure, combined
with transformation approach, can be cut into particular device shapes for
acoustic cloaking and illusion.
