Transformer-based input integrated matching in cascode Amplifier: Circuit analysis and comparison with inductive degeneration

A circuit analysis of the Low Noise Amplifier (LNA) topology with transformer-based input integrated matching is carried out. The analytical expressions for input impedance, transconductance gain and noise figure have been derived and compared with those of the most widespread LNA topology, i.e. the cascode LNA with inductive degeneration. Finally, two LNAs operating at 24 GHz have been designed in 28nm FDSOI CMOS with the two input integrated matching techniques, under the same conditions for a verification and direct comparison.