Compact artificial line phase shifter on ferroelectric thick-film ceramics

An artificial transmission line based on Barium-Strontium-Titanate (BST) thick-film is used as a phase shifter in this work. The benefits of artificial transmission lines are exploited to realize a very compact phase shifter with a length of 3mm for 342° differential phase shift. The prototyped phase shifter exhibits a figure of merit (FoM) of 52°/dB in the frequency range 8-10 GHz. The proposed circuit is fabricated in only one photolithography process cycle on a low cost screen printed thick-film ceramic.