Design and Investigation of Ferroelectric Digital Phase Shifter

A reflection type phase shifter based on a tunable ferroelectric capacitor is under consideration. A design and characteristics of the one-bit ferroelectric phase shifter is proposed and discussed. The minimal insertion loss of the phase shifter is limited by the commutation quality factor of the capacitor and can be achieved in the case when the losses of the phase shifter in both states have the same value. The layout of the phase shifter based on a coplanar waveguide structure is shown. Measured characteristics of the phase shifter are compared with the predicted ones.