Distortion in RF CMOS short channel low noise amplifiers

An approach to estimate the distortion in CMOS short-channel (0.18 /spl mu/m gate length) RF low noise amplifiers (LNA), based on Volterra's series, is presented. Compact and accurate frequency-dependent closed form expressions describing the effects of the different transistor parameters on harmonic distortion are derived. For the first time, the second order distortion (HD2), which is crucial in homodyne receivers, is studied. The analytical analysis is verified through simulations and measured results of a 0.18 /spl mu/m CMOS 5.8GHz folded-cascode LNA prototype chip geared towards sub-IV operation. Distortion-aware design guidelines for RF CMOS LNA's are provided throughout the paper.