A steerable leaky-wave antenna using a tunable impedance ground plane

A steerable leaky-wave antenna is built using a mechanically tunable impedance surface. A horizontally polarized antenna couples energy into leaky transverse electric waves on a tunable textured ground plane. By tuning the resonance frequency of the surface, the band structure is shifted in frequency, which changes the tangential wave vector of the leaky waves for a fixed frequency. This steers the elevation angle of the resulting radiated beam. This steerable leaky-wave antenna can scan over a range of 45/spl deg/ using a mechanical movement of about 1/500 wavelength.