2-Bit MEMS distributed X-band phase shifters

A wideband distributed coplanar-waveguide (CPW) phase shifter has been deve loped for X-band operation, The design is based on the distributed MEMS tra nsmission Line (DMTL) loaded with MEMS bridges and MIM capacitors. A 2-bit distributed phase shifter was fabricated on a 500-mum quartz substrate, and achieved a true-time delay operation from 1 to 20 GHz with a reflection co efficient less than -11 dB from 2 to 20 GHz and above. Insertion loss is do minated 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 ph ase shifter with wideband performance at X-band frequencies.