77-79 Ghz Stacked Low Noise Amplifier for Automotive Radar

This paper describes the three stage stacked low noise amplifier for automotive radar applications. Stack structure is employed to overcome the inability of MOSFETs to operate at high voltage levels, as stacked MOSFETs can tolerate k × V max where V max can be chosen to be near the breakdown voltage of a single device. Realized in 65nm CMOS process, the stacked amplifier provides a gain of 15 dB with noise figure of 3.5 dB at 79 GHz. The amplifier draws 28.2 mA current from a 3V supply. To examine the nonlinear behavior of the amplifier Volterra analysis is performed, second and third order harmonic distortions are determined. The effect of feedback on the output resistance is examined using Blackman’s analysis. Sensitivity analysis of the stacked LNA is also performed to determine the effect of parameter variations on the circuit performance.