Reflectivity of planar metallic fractal patterns

We studied the reflective properties of a small dielectric plate covered with a fractal-like metallic pattern generated by a particular type of space-filling curves. We found, both experimentally and theoretically, that the plate can reflect electromagnetic waves in a multitude of frequencies, generated from a near-field monopole antenna. Some of the reflected waves have wavelengths much larger than the lateral dimension of the plate. In comparison, a metal plate of the same size failed to reflect when its lateral size was smaller than half of the corresponding wavelength.