An ultra-low-power RF transceiver with a 1.5-pJ/bit maximally-digital impulse-transmitter and an 89.5-μW super-regenerative RSSI

This paper proposes an RF transceiver with a maximally-digital impulse transmitter (I-TX) and a superregenerative received-signal-strength-indicator (RSSI) circuit for wireless sensor network (WSN) application. Our I-TX enables strict bit-level duty cycling operation to achieve both ultra-low power consumption and superior energy-per-bit in kb/s to Mb/s range. The proposed RSSI for low-power localization and low-rate downlink measures input power by exploiting the phenomenon that the oscillation start-up time logarithmically accelerates as input power increases. The I-TX fabricated in a 65nm CMOS achieves energy-per-bit of 1.5 pJ/bit at 10 Mb/s which is better than previous works. The proposed RSSI with -85 dBm sensitivity consumes 89.5 μW with modest dynamic range and linearity.