Modulated Reactance Surfaces for Leaky-Wave Radiation Based on Complete Aperture Field Synthesis

A design technique for modulated surface reactances for 1-D leaky-wave antenna applications based on complete aperture field synthesis is presented. For a given visible-region spectrum corresponding to desired radiation and polarization patterns, the evanescent or invisible-region spectrum is introduced and systematically optimized to render the antenna surface passive and lossless everywhere, while generating the specified far-zone characteristics. Design techniques for linear and circular polarizations excited by a TM-polarized feed surface wave are provided together with design examples with simulation validation. Not based on local periodicity, the proposed technique does not suffer from limitations associated with the traditional sinusoidally modulated reactance surfaces.