Effect of Degeneration on a Millimeter Wave LNA: Application of Microstrip Transmission Lines

This paper presents the impact of a singlewire degeneration microstrip transmission line (MTL) on the gain and noise figure of a millimeter wave low noise amplifier (LNA) at 60 GHz, designed using 0.13 μm SiGe BiCMOS technology. To accomplish this, the performance of the designed LNA is varied with and without the presence of singlewire degeneration MTL in a setup at the first stage of the LNA, using a common emitter transistor topology. Initial results show that the introduction of the singlewire degeneration MTL in the schematic resulted in a decrease in the gain and an increased noise figure of the LNA, while without the presence of a singlewire MTL, the common emitter transistor of the cascode configuration gave rise to a satisfactory increase in gain and reduced noise figure for the LNA. A maximum gain of 15.91 dB and a minimum noise figure of 6.74 dB were recorded when MTL was added to the LNA circuit, while a maximum gain of 20.84 dB and a minimum noise figure of 6.16 dB was recorded when the singlewire MTL was disconnected.