A Low-Power,$X$-Band SiGe HBT Low-Noise Amplifier for Near-Space Radar Applications

A low-power, X-band low-noise amplifier (LNA) is presented. Implemented with 180 GHz silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs), the circuit occupies 780times660 mum
²
. The LNA exhibits a gain of 11.0 dB at 9.5 GHz, a mean noise figure of 2.78 dB across X-band, and an input third-order intercept point of -9.1 dBm near 9.5 GHz, while dissipating only 2.5 mW. The low-power performance of this LNA, together with its natural total-dose radiation immunity, demonstrates the potential of SiGe HBT technology for near-space radar applications