Performance investigation of dual band millimetre wave SiGe low noise amplifier (LNA)

SiGe HBT technology transistor provides performance comparable with III-V technologies along with the processing maturity and integration levels commonly associated with Si technology. The present work utilizes 130nm SiGe HBT transistors to investigate the performance of low noise amplifier (LNA) for 40GHz and 60GHz wireless personal area networks (WPANs). The transfer gain S2i was found >9dB with 3-dB bandwidth (BW)>5GHz in the bands of interest. Excellent simultaneous matching at input (S11≤-20dB) and output (S22≤-10dB) with noise figure (NF)<;2.5dB at both the bands were obtained. Theoretically, predicted S-parameters of the LNA were found closely matched with corresponding simulated results. The input third-order intercept (IIP3) was found > 3.0dBm in the bands of interest. The graph of performance ratio (R=S21/PDC) versus noise factor F gives significant advantage for SiGe HBT LNA (i.e. achieve high R at low F) as compared to GaAs HBT and Si CMOS technologies. A new figure-of-merit (FoM) involving S2i, noise factor F, IIP3 and power consumption PDC was found to be significantly higher for SiGe LNA than a previously published experimental result for silicon CMOS LNA.