Patent attributes
An apparatus includes a traveling-wave antenna array comprising a plurality of adjacent metamaterial surface antennas comprising a waveguide or a cavity, each adjacent metamaterial surface antenna comprising an array of metamaterial radiators coupled to a surface of the waveguide or the cavity, each metamaterial radiator comprising an individually addressable tunable component that can be tuned over a spectral bandwidth to generate different radiation patterns. The apparatus further includes a phase diversity feed coupled to the traveling-wave antenna array and configured to provide adjustable phase diverse input to two or more of the plurality of adjacent metamaterial surface antennas, the phase diverse input comprising a first phase for a first traveling-wave antenna and a second phase for a second traveling-wave antenna, the first phase being different from the second phase, wherein the phase diverse input is-selected to suppress grating lobes for a directed beam pattern selected for transmission.