Design and Simulation of a 3GHz SiGe HBT Based Low Noise Amplifier for S-Band Applications

This paper presents the design, simulation, and performance analysis of a Low Noise Amplifier (LNA) at 3 GHz for S-band RF receiver front-end applications. The LNA employs the Silicon-Germanium Heterojunction Bipolar Transistor (SiGe HBT), selected for its high transition frequency <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(f_{T})$</tex>, superior linearity, and inherently low noise figure. The design process was performed in Keysight's Advanced Design System (ADS) for characterization and performance analysis. This design achieved significant performance at desired frequency of 3 GHz for lumped and distributed components respectively. The LNA includes an impressive power gain <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(S_{21})$</tex> of 33.409 dB, a low minimum Noise Figure <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(N F_{\text{min }})$</tex> of 0.931 dB, and excellent input and output matching <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(S_{11}&lt;-19 d B, S_{22}&lt;-14 d B)$</tex>. The unconditional stability of the design, confirmed by a stability factor <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$K=1.807$</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mu = 2.023$</tex>, which is suitable for <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$R F$</tex> receiver front-end.