Wire lens antennas with near/far field conjugation properties

Imaging properties of a wire phase conjugating (PC) lens operating in the near or far field of the source are studied in this paper. The near field lens operates as a standalone device while the far field PC lens is augmented with scatterers on both the source and image sides. These scatterers permit evanescent-to-propagating spectrum conversion and reverse, propagating-to-evanescent, process thus the sub-wavelength information encoded into propagating waves on the source side is extracted back on the image side. In the near field lensing scenario we discuss the role of negative refraction due to phase conjugation and wire lens inductive loading. All stages of far field imaging - evanescent-to-propagating spectrum conversion, focusing properties of a wire PC lens and source reconstruction by the propagating-to-evanescent spectrum conversion are analyzed analytically and by using numerical simulations. The results obtained in the paper demonstrate unique opportunities offered by PC lenses in creation of imaging devices operating in both near and far field zone of the imaged electromagnetic source.