Meander line millimetre-wave liquid crystal based phase shifter

A liquid crystal (LC) based inverted microstrip meander line phase shifter is presented. The control of phase shift is achieved through use of an external electric field. To facilitate on-wafer measurements and the application of the electric field to the LC, a specially developed transition from the inverted microstrip line to the CPW is used. The performance of the proposed meander line phase shifter is tested using two LC mixtures: first, the standard LC mixture, commonly referred to as E7, while the second mixture is known as MDA-00-3506. A differential phase shift of 202° is achieved with the phase shifter using E7 and 270° using MDA-00-3506 at 50 GHz for a 50 mm-long microstrip line meandered into a length of 7.67 mm. The results are discussed.