The effect of coordinate transformation function on scattering characteristics of cylindrical cloaks with a quantity of discrete layers

• Minimizing scattering fields for cloaks with only a few quantity of discrete layers.
• An optimal scheme is obtained, which is unlike the method for near ideal models.
• The effects of the interfaces between discrete layers of the cloak are discussed.

We studied the electromagnetic scattering from cylindrical cloaks with a quantity of discrete homogeneous layers. The scattering cross sections (SCS) of electromagnetic cloaks designed by different coordinate transformation function are discussed by using a polynomial transform function. The results show that besides the inner boundary, the interfaces between the adjacent discrete anisotropic layers inside the cloak also affect its performance. Through the proper design of the coordinate transformation order, the electromagnetic field distribution insides the cloak can be optimized and the invisible performance of the cloak could be improved with minimization of SCS. These results provide a better way of designing the cloak to achieve low scattering with only a few layers of anisotropic metamaterials.