A 3-10GHz bandwidth low noise amplifier for ultra-wideband application using SiGe HBT technology

A feedback topology low-noise amplifier (LNA) using advanced SiGe HBT technology for application in ultra-wideband (UWB) systems is presented in this paper. The design consists of single stage topology in two feedback loops to achieve broadband gain together with low noise figure (NF) and good input and output impedance match. Using 0.35 mum SiGe HBT process, the simulated results show 11.9 dB of gain(S
₂₁
) with 1.7 dB of variation over the 3 GHz to 10 GHz band, and a low NF ranging from 3.6 dB to 3.98 dB while consuming a dc power of only 10 mW. The matched input and output reflectance (S
₁₁
and S
₂₂
) are less than -5 dB and -10 dB respectively. At the same time, LNA is unconditionally stable over the entire band.