Advances in anisotropic artificial impedance surfaces

The interaction between an object and electromagnetic waves can be described in terms of its surface impedance. By introducing large anisotropy into artificial impedance surfaces, it is possible to achieve a high degree of control over this interaction that is not possible with isotropic surfaces. These surfaces can be used to create nonscattering surface waveguides, beam shifting structures, and to control scattering from edges and other features. With new patterning techniques we can obtain arbitrary and smoothly varying impedance functions for even greater control.