Noise figure measurement of three-port differential low-noise amplifiers
A measurement procedure to de-embed the noise figure (NF) of a three-port differential low-noise amplifier (LNA) from single-ended (SE) measurements is presented. An approximate solution for the differential NF is found in terms of two SE noise figure and gain measurements and the sensitivity of the de-embedded NF to unsymmetrical performance is analysed. The theory presented is applied to a three-port differential LNA and the de-embedded NF is compared to that of an equivalent SE LNA design. © 2012 The Institution of Engineering and Technology.