Suppressing the Electromagnetic Scattering With an Helical Mantle Cloak

Following our recent findings on achieving invisibility and transparency using low-profile mantle cloaks, we propose a practical implementation of an RF cloak made of a simple metallic helical sheath, whose anisotropic surface impedance can provide scattering cancellation for dielectric cylinders over a moderately broad bandwidth. By properly selecting the pitch angle of the con- ducting helix, the effective surface reactance is tailored to drastically suppress the scattering from a dielectric infinite cylinder. This simple but effective surface cloaking technique may be of particular interest to low observability and camouflaging, noninvasive probing, and low-interference communications.