Perfect Conformal Plane-Wave to Surface-Wave Couplers

Perfect plane-wave to surface-wave couplers over non-planar port regions are designed. The conformal couplers transfer all of the available power in the incident beam to the surface wave which delivers it to a spatially dislocated output port. At the output port, the surface wave is leaked as a beam with control over its amplitude and phase. As all of the captured power is leaked into the reradiated beam, the transfer efficiency is near unity. The metasurfaces consist of an arbitrarily shaped impedance sheet supported by a grounded dielectric spacer. The design occurs in three phases, an integral equation modelling/method of moment solution stage often resulting in the need for active and/or lossy unit cells, a subsequent optimization phase to remove the need for loss and/or gain rendering the metasurface passive and lossless, and a final unit cell design stage to translate the purely reactive impedance sheet to printed circuits. The couplers can be useful in new high frequency communications systems to increase fields in shadow zones where diffraction strengths are reduced, or for new conformal cloaks, electromagnetic illusions, and camouflage.