Monolithic-Integrated MEMS-Tunable Reflective Cell for Ku-Band Mobile Satellite Two-Way Connectivity

This paper presents the design and measurement of a single-layer micro-electromechanical system (MEMS)-tunable reflective unit cell with orthogonally polarized dual bands for Ku-band mobile satellite connectivity. Six capacitive MEMS switches across each slot of a cross-slotted patch tune its reflection phase at 12 GHz (reception) with vertical polarization and 14 GHz (transmission) with horizontal polarization. This unit cell provides four phase states with overall phase swing of 200° and 180° and average reflection amplitude of -0.79 and -0.69 dB at the lower and upper bands, respectively. This unit cell can be used for generation of an independently controlled beam at each of its operating bands. A monolithic process is also developed for the fabrication of this reflective cell along with the dedicated dc bias network. For unit cell measurements, a custom-designed waveguide setup with four DC pins was fabricated for simultaneous and independent control of all MEMS switches. The measurement results are in good agreement with simulations.