A Feed-Forward Gain Enhancement Technique in a Narrow-Band Low Noise Amplifier Using Active Inductor

Abstract

This paper presents a novel active inductor-based low noise amplifier (LNA), which is capable of achieving high gain and low noise figure (NF) in a small die area. The proposed design consists of two stages. The first part comprises a modified cascode stage containing dual common source transistors. The authors replaced the passive drain inductor with an active inductor to make the circuit area-efficient. The second part consists of a feed-forward path (FFP), which boosts the gain and reduces the NF of the modified cascode stage. The post-layout simulations of the 2.4 GHz LNA in 180 nm CMOS technology, using cadence virtuoso, demonstrate the performance improvement in terms of gain, NF and area. The NF, power gain and IIP3 of the amplifier are 0.402 dB, 14.11 dB and -13.45 dBm, respectively. The power consumption is 5.63 mW from a 1.8 V power supply. The area of the core is 0.002 mm $$^2$$ . The FFP enhances the gain by 12.2% and reduces the NF by 7.2% compared to the modified cascode LNA. The figure-of-merit shows that the designed amplifier is around two times better than the previously reported ones.