A Novel Duality Between Permeability and Permittivity in a Concentric Sphere
Noushin Vaseghi
Ali Abdolali
Homayoon Oraizi
Consider a TEM plane wave incident on a spherical multilayer structure, then the following theorem is valid. This theorem reveals a duality between permeability and permittivity of media in a spherical multilayer structure. Theorem: Consider a sphere with arbitrary radius and parameters s (ε2,μ2) surrounded by a homogenous medium with parameters (ε1,μ1). Then consider the case that each medium is filled by its dual medium according to the interchange εi↔μi. Then, the forward and backward radar cross sections of the structure are the same for the two dual cases. However, in half planes φ=((2k+1)π)/4;(k=0,1,2,3), the interchange εi↔μi has no similar effect on the value of the radar cross section.