Reconfigurable MEMS-enabled RF Circuits for Spectrum Sensing

The desire for low power multifunction radios for the DoD is driving interest in reconfigurable RF architectures. While software reconfiguration is the ultimate goal, data conversion power and dynamic range limitations imply that some of the reconfiguration has to take place in hardware. Two RF reconfigurable hardware components that can be integrated onto a single chip will be described in this paper. A mechanically reconfigurable capacitor is integrated with a high Q inductor for MEMS-based LC filters that can switch between 2.6 and 3.45 GHz and VCOs that have 5x less power consumption comparable to other similar VCOs. Electromechanical resonator-mixers that can simultaneously downconvert GHz input frequencies and mechanically filter with Q > 2000 are arrayed to enable reconfiguration by electrical selection of a resonator-filter in the array. A two-level reconfigurable radio architecture that takes advantage of these components is introduced, and its potential use in spectrum sensing is described.

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