| 摘要 |
<p>A phase shifter (16) for use in a phased array antenna includes a waveguide flange of metallic material has a narrow slot (30) formed therein, the slot having ferroelectric material (18) disposed uniformly therein. The slot is of reduced height relative to normal waveguide dimension, such height reduction minimizing the voltage applied across the material. RF energy radiating from a source is directed to pass through the ferroelectric material. A single, thin conductive plate (20) is disposed in the center of the slot, the plate having an electrical DC voltage imposed thereon. Such voltage creates an electric field across the material, which for uniaxial ferroelectric orients the optic axis in a direction which is both normal to the direction of propagation of the radiation and parallel to the polarization direction of the radiation. The electric field changes the wave propagation constant (i.e., for a uniaxial ferroelectric, the extraordinary wave refractive index, ne), producing a varying path length of the radiation in the material, resulting in a controllable alteration of the radiation phase. The varying phase shift is either used to control an antenna's radiating direction, or is detected by a measuring device to test the material itself.</p> |
