Title :
2-bit MEMS distributed X-band phase shifters
Author :
Hayden, J.S. ; Rebeiz, G.M.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA
Abstract :
A wideband distributed coplanar-waveguide (CPW) phase shifter has been developed for X-band operation. The design is based on the distributed MEMS transmission line (DMTL) loaded with MEMS bridges and MIM capacitors. A 2-bit distributed phase shifter was fabricated on a 500-μm quartz substrate, and achieved a true-time delay operation from 1 to 20 GHz with a reflection coefficient less than -11 dB from 2 to 20 GHz and above. Insertion loss is dominated by a low-Q MIM capacitor (14 at 10 GHz) and the effect of this Q is shown, Increasing the MIM capacitor Q will result in an excellent 2-bit phase shifter with wideband performance at X-band frequencies.
Keywords :
MIM devices; Q-factor; capacitors; coplanar waveguide components; distributed parameter networks; micromechanical devices; microwave phase shifters; 1 to 20 GHz; 500 micron; MEMS bridges; MEMS distributed phase shifters; MIM capacitors; SiO/sub 2/; X-band phase shifters; coplanar-waveguide phase shifter; distributed MEMS transmission line; low-Q capacitor; quartz substrate; wideband distributed CPW phase shifter; Bridge circuits; Coplanar transmission lines; Coplanar waveguides; Delay; Insertion loss; MIM capacitors; Micromechanical devices; Phase shifters; Reflection; Wideband;
Journal_Title :
Microwave and Guided Wave Letters, IEEE
