X- and K-Band SiGe HBT LNAs With 1.2- and 2.2-dB Mean Noise Figures

This paper presents low-noise amplifiers (LNA) at X- and K-band frequencies in a 0.18- μm SiGe HBT technology. A method of noise match optimization with respect to base inductance in SiGe LNA design with large transistors is proposed. The measured X- and K-band LNAs result in 1.2- and 2.2-dB mean noise figure in their frequency bands, with an associated peak gain of 24.2 and 19 dB at 8.5 and 19.5 GHz, respectively. The measured IIP₃ is -11 and -4 dBm at 10 and 20 GHz, for a power consumption of 32.8 mW (X-band LNA) and 22.5 mW (K-band LNA). To the authors´ best knowledge, these results outperform all available CMOS designs and achieve the lowest mean noise figure at X- and K-bands in any SiGe or CMOS process. The main application areas are in low-noise receivers for terrestrial communication systems and low-cost radars.