Microwave Variable Phase Shifter of Coplanar Waveguide Using Ferroelectric Liquid Crystal

A microwave variable phase shifter of a coplanar waveguide with floating electrodes using a ferroelectric liquid crystal is discussed. The electric field of the microwave is calculated in the phase shifter and the electric wave propagation of the coplanar waveguide mode is confirmed. The measured phase shift is proportional to the microwave frequency and the anisotropy of the refractive index in the microwave region is estimated to be 45% of that in the visible region. The measured phase shift increases with increasing applied voltage from an offset voltage. The response time is less than 1.6 ms, and a high-speed microwave variable phase shifter is realized.