W -band RF -MEMS switches, phase shifters and antennas.

Abstract

RF MicroElectroMechanical Systems (RF-MEMS) have been demonstrated up to 50 GHz with excellent performance. This thesis will focus on extending the MEMS to the W-band frequency range (75--110 GHz) by developing some of the basic front end components in telecommunications and radar systems: switches, phase shifters and antennas. W-band CPW MEMS capacitive switches are first developed with a very low loss (-0.2 to -0.5 dB) and a high isolation (-30 dB). These switches are then used to implement low loss (1.75 dB/bit) switched-line phase sifters that cover the 75--100 GHz range. These RF components outperform their solid-state-based counterparts by a large margin. RF-MEMS switches and phase shifters are also implemented in a microstrip configuration without via-holes with excellent insertion loss, but a limited bandwidth of operation. The power handling and associated thermal analysis of RF-MEMS capacitive switches are investigated in this thesis, and it is shown that capacitive switches can easily handle 1--2 W of RF power without any thermal limitations. Finally, W-band micromachined tapered-slot antennas are demonstrated on silicon substrate with radiation patterns similar to the antennas on low dielectric constant substrates.