A 127-163 GHz LNA with in-band 21-dB gain and 6.8-dB NF in a 55-nm SiGe BiCMOS technology

This article presents the design of a low-noise amplifier (LNA) in a $55-\mathrm{nm}$ SiGe BiCMOS technology targeting high-data-rate applications. The sizing and biasing of the heterojunction bipolar transistor (HBT) are discussed and a design flow is proposed which avoids the systematic use of electromagnetic (EM) solvers. On the one hand, a parametric model for transmission lines addresses the need for design variables while having a good correspondence with EM simulations. On the other hand, a graphical method is proposed to realize a trade-off between noise and conjugate input impedance matching. A complete postlayout simulation of the LNA is performed, showing a 127 163 GHz bandwidth, with a maximum gain of 24 dB and a noise figure below 6.8 dB for $20-\mathrm{mW}$ power consumption. Passive components such as capacitors are measured and compared to the EM simulations.