1.2V sub-2dB NF Quasi-differential Wideband LNA using Complementary Post-distortion

This paper presents a self-biased current-reuse low noise amplifier (LNA) using self-cascode transistors, to obtain higher gains at lower supply voltages. Quasi-differential configuration is used to achieve high linearity and common-mode rejection. Complementary post-distortion (CPD) technique is also proposed to minimize the third order non-linearity of the LNA. The proposed LNA implemented in 65nm UMC low leakage CMOS process technology with a 1.2V supply occupies a core area of 0.01mm
²
. The LNA without CPD has low NF (1.42–1.65dB) and good gain (18.4–20.6dB) at low power dissipation (1.98mW) in the 3.25–4.5 GHz frequency band. The average 2
^nd
order input intercept point (IIP2), 3
^rd
order input intercept point (IIP3), and 1dB compression point (P
1dB
) are (+48.53dBm, +0.172dBm, −14.53dBm). Monte Carlo simulations of IIP3 are within ±2σ. The LNA with CPD achieves significant improvement in the average P
1dB
(+3.72dBm) and average IIP3 (+3.18dBm) at the cost of higher power dissipation (+0.6mW).