Waveguide Antenna Applications of Metamaterials to Leaky-Wave Slotted Waveguide Array

Effective guided wavelength can be controlled in both negative and positive by metamaterials. Metamaterials are applied to some kinds of slotted waveguide leaky-wave array antenna. First, left-handed waveguide leaky-wave slot array antenna is developed by using perturbation waveguide circuits for phase advance. Beam scanning performance is obtained and the beam direction is controlled by changing the stub length mechanically. In order to suppress grating lobes of the slotted waveguide array antenna, an effective guided wavelength is designed to be shorter than the wavelength in free space. Fundamental feasibility in the waveguide antenna application of metamaterials is confirmed in this paper.