Comments on "CMOS low-noise amplifier design optimization techniques"

The original paper by T.-K. Nguyen et al. (see ibid., vol.52, no.5, p.1433-42, May 2004) analyzes the four low-noise amplifier (LNA) design techniques, i.e.: 1) classical noise matching; 2) simultaneous noise and input matching (SNIM); 3) power-constrained noise optimization; and 4) power-constrained simultaneous noise and input matching (PCSNIM) based on the noise parameter expressions so as to provide the guideline for LNA designers. Unfortunately, there are some errors in the derivations of noise parameter expressions for the SNIM, which also applied to the PCSNIM.