Double sided nonlinear FSS for microwave phase conjugation and source imaging

Microwave phase conjugation has been extensively studied both theoretically and experimentally (Brabetz, T. et al., IEEE Trans. MTT, vol.49, no.3, p.465-9, 2001), for use in retrodirective communication systems. However it can be arranged that a phase conjugated forward (transmitted) signal could also be generated, leading to applications in microwave lensing. We propose the concept and analyze a double sided frequency selective surface with phase conjugation properties which can be implemented using retrodirective antenna array techniques (Brabetz et al.). We show "negative refraction" of a transmitted plane wave signal by a double sided array and we illustrate the possibility of line source imaging using such a structure formed by densely packed double periodic wire arrays.