A high sensitivity and low power envelope detector for wireless sensor nodes

In this paper different parts of a wake-up receiver for wireless sensor node are presented. The circuit is composed of an amplifier with input impedance matching network and an envelope detector both working at 868 MHz. The amplifier is incorporated in order to increase the sensitivity of the wake-up receiver. The amplified signal passes to the envelope detector which demodulate on-off keying signal at 125 kHz. The circuits have been designed to optimize power consumption and area. The total power consumption and the minimum signal detected are 44.32 uW and 0.4 mVp respectively. The circuits were implemented in UMC CMOS 65 nm process.