On the Accuracy of the Uniform Asymptotic Physical Optics Solution for the Diffraction by a PEC-DNG Metamaterial Junction

The effectiveness of the uniform asymptotic physical optics approach is tested with reference to the plane wave diffraction by a nonplanar junction that is formed by a perfect electrically conducting sheet and a lossy double-negative metamaterial layer. In particular, attention is paid to the accuracy of the total field that is obtained by adding the geometrical optics contributions to the diffraction one. Numerical tests and comparisons with full-wave numerical simulations are performed to assess the limits of validity of the approach.