Degree Granting Department
Dr. Tom Weller.
Tunable, Transmission lines, Phased array, Calibration, Slow-wave
A true time delay multi-bit MEMS phase shifter topology based on impedance-matched slow-wave CPW sections on a 500 m thick quartz substrate is presented. Design equations based on the approximate model for a distributed line is derived and used in optimization of the unit cell parameters. A semi-lumped model for the unit cell is derived and its equivalent circuit parameters are extracted from measurement and EM simulation data. This unit cell model can be cascaded to accurately predict N-section phase shifter performance. Experimental data for a 4.6mm long 4-bit device shows a maximum phase error of 5; and S11 less than -21dB from 1-50GHz. A reconfigurable MEMS transmission line based on cascaded capacitors and slow-wave sections has been developed to provide independent Zo - and -tuning. In the Zo-mode of operation, a 7.4mm long line provides Zo-tuning from 52 to 4 (+/-2;) with constant phase between the states through 50GHz.
Scholar Commons Citation
Lakshminarayanan, Balaji, "Low loss rf/mm-wave mems phase shifters" (2005). Graduate Theses and Dissertations.