Radiation pattern synthesis using impedance surfaces supporting leaky waves

We report impedance surfaces that offer subwavelength control of the leakage constant a_x and propagation constant ß_x. This enhanced control allows tailoring of the aperture field at the impedance surface and therefore the synthesis of arbitrary far-field patterns. The transverse resonance technique is used to analytically relate the complex wavenumber k_x to the electrical parameters of the proposed impedance surface. Two design examples are reported: a constant amplitude aperture distribution for increased directivity, and a Hamming window amplitude distribution for reduced sidelobe levels.