A quasi-millimeter wave band phase shifter with MEMS shunt switches

As a key component of high-performance phased array antennas, a variable phase shifter using MEMS (microelectromechanical systems) switches have been studied. A monolithically-integrated 180° phase shifter was designed for quasi-millimeter wave band, and fabricated on a Si GCPW (grounded coplanar waveguide) substrate with ground vias filled with conductive paste. The Si GCPW substrate with dummy MEMS switches, i.e. short and open lines, showed the maximum insertion loss as small as 1.65 dB and a phase shift of 184.6° at 24 GHz. The 180° phase shifter with the integrated switches showed an almost identical phase shift of 184.2°.