Advances in the design of Jaumann absorbers

The authors consider electric screens with the material spacers assumed homogeneous, nonmagnetic, lossless, commensurate, and isotropic. Normal incidence is assumed. Such an N-layered structure may be modeled as a transmission line network. The unknowns are the N spacer characteristic impedances and the N sheet surface resistivities. All are normalized by the free-space impedance. The maximally flat solution of Fante and McCormack (1988) is extended to any number of layers, with proven solvability up to 20 layers. An equiripple solution, which, for a given number of layers and specified maximum reflection coefficient, exhibits a wider bandwidth than the corresponding maximally flat solution, is described. The sheet resistivity spread is also much narrower, thus increasing realizability.<>