A 10–110 GHz LNA with 19-25.5 dB Gain and 4.8-5.3 dB NF for Ultra-Wideband Applications in 90nm SiGe HBT Technology

This paper presents a broadband differential low-noise amplifier (LNA) at 10–110 GHz. The four-stage LNA is realized using 90 nm SiGe BiCMOS process having a 300 GHz f T HBT. Resistive feedback is used for operation at 10–50 GHz, and a wideband collector load with a linear impedance increase versus frequency compensates for the transistor output capacitance and guarantees a monotonic increase in the gain from 60 to 100 GHz. The LNA has a measured small-signal gain of 19-25.5 dB and the measured noise figure (NF) is 4.8-5.3 dB at 10–50 GHz. The LNA also achieves an output-referred 1dB compression point (OP1dB) of −3.3 dBm at 66 GHz. The differential LNA consumes 96 mW (48 mW half circuit) with an active circuit area of $1.3 \times 0.6\ \text{mm}^{2}$ . Application areas are in wideband receivers and in wideband microwave and millimeter-wave instrumentation systems.