Spring 2014 IAB & Research Review
March 5 - 6
Micromechanical Frequency Divider
A capacitive-gap RF MEMS resonator array demonstrates a first on-chip MEMS frequency divider with 61-MHz output generated from a 121-MHz electrical drive through use of a parametric oscillation effect. This provides not only the expected 6dB reduction in close-to-carrier phase noise, but also a remarkable 23dB reduction in far-from-carrier noise due to filtering by the high-Q mechanical resonator. In contrast with traditional frequency division, the parametric oscillator here requires no active devices, adds no noise to the signal and has essentially zero power consumption, limited in principle only by MEMS resonator loss.