A 2.5-dB NF 3.1–10.6-GHz CMOS UWB LNA with small group-delay-variation

A 3.1-10.6-GHz ultra-wideband low-noise amplifier (UWB LNA) with excellent phase linearity property (group-delay-variation is only plusmn16.7 ps across the whole band) using standard 0.13 mum CMOS technology is reported. To achieve high and flat gain and small group-delay-variation at the same time, the inductive peaking technique is adopted in the output stage for bandwidth enhancement. The UWB LNA dissipates 10.68 mW power and achieves input return loss (S₁₁) of -17.5 ~ -33.6 dB, output return loss (S₂₂) of -14.4 ~ -16.3 dB, flat forward gain (S₂₁) of 7.92 plusmn 0.23 dB, and reverse isolation (S₁₂) of -25.8 ~ -41.9 dB over the 3.1-10.6 GHz band of interest. State-of-the-art noise figure (NF) of 2.5 dB is achieved at 10.5 GHz. The measured 1-dB compression point (P_1dB) and input third-order inter-modulation point (IIP3) were -14 dBm and -4 dBm, respectively, at 6 GHz.