A 0.69-mW Sub-Sampling NB-IoT Receiver Employing a Linearized Q-Boosted LNA

This paper presents a receiver for NB-IoT that eliminates the need for an RF local oscillator (LO) via a sub-sampling architecture. A pseudo-balun Q-boosted LNA provides sharp anti-aliasing filtering with a noise figure (NF) of 5.6 dB. A direct-coupling derivative superposition technique where low-Vt and thick-gate transistors with opposite non-linear characteristics are combined to improve the measured IIP3 by 7 dB to -18 dBm with little NF overhead. Fabricated in 65 nm CMOS, the entire receiver, including the LNA, a S/H circuit and a 10-bit SAR ADC, consumes only 0.69 mW while meeting NB-IoT specifications.