A Sub-mW Fully Integrated Wide-Band Receiver for Wireless Sensor Network

This letter presents low power implementation of a fully integrated wide band receiver for wireless sensor network. The receiver targets extremely low power operation with wide band coverage. Fabricated in 28 nm CMOS process, the receiver employs a passive mixer-first RF front-end with zero-IF architecture which is driven by non-overlapping four-phase local oscillator (LO). To minimize power consumption in LO driving stage which consumes the largest portion of power in this structure, supply voltage and device size optimization techniques are introduced. Enhanced non-overlapping LO circuit is proposed to prevent degradation of the noise figure. The receiver also includes a low power base band amplifier and in-band noise reduced biquad filter. The total receiver chain achieves conversion gain of 55 dB, noise figure of 13.6 dB and IIP3 of -7.5 dBm (@10 MHz spacing) with power consumption under 1 mW at the frequency band of 0.85 ~ 2.55 GHz.