A CMOS differential noise cancelling low noise transconductance amplifier

In this paper a two stage CMOS Radio Frequency (RF) low noise transconductance amplifier is proposed. The feed-forward noise-cancelling technique is exploited to improve the Noise Figure (NF). Simulations with 45 nm CMOS process have been performed to verify the proposed design. The LNA achieves a transconductance of 115 mS, -3 dB bandwidth of 4.5 GHz, NF of 3.4 dB and IIP3 of -10 dBm. Compared to the single stage transconductance amplifier, the in band NF improves by 3.3 dB. The power consumption is 40 mW.