Self-biased resistive-feedback current-reused CMOS UWB LNA with 1.7dB nf for IR-UWB applications

In this paper, a self-biased resistive-feedback current-reused CMOS low-noise amplifier (LNA) is presented for impulse-radio ultra-wideband (IR-UWB) applications. Wideband input, inter-stage, and output matching are achieved by using two stages of resistive-feedback amplifiers with inductive peaking. Consequently, high and flat power gain (S21), low and highly-flat noise figure (NF), and small group-delay variation are simultaneously achieved. By employing resistive-feedback, not only wideband matching is guaranteed, but also both stages adopt self-biasing technique (power and area saving) which totally removes noise contribution of bias circuitry at the input (better NF performance). As a result, state-of-the-art NF of 1.7dB (@7GHz) is achieved where across the whole frequency band of interest (i.e., 3-11GHz) NF remains below 2 dB. A flat S21 of 12.9±0.45dB and small group-delay variation of 68.5±17.5ps are also achieved. The proposed UWB LNA dissipates 10.35mW under supply of 1.5V in 0.18μm CMOS technology.