An Integrated RF-Powered Wake-Up Wireless Transceiver With –26 dBm Sensitivity

This article presents a fully RF-powered wireless transceiver integrating an efficient RF energy harvester (RFEH), a Wake-up Receiver (WuRx), and a Wake-up Transmitter (WuTx) on a single CMOS chip. The WuRx is designed to operate with supply voltages as low as 300 mV allowing to be entirely powered up by the RF energy at power levels as low as −26 dBm. The capability of the WuRx to operate without using a power management unit (PMU) enhances the sensitivity and overall conversion efficiency of the RFEH system. By utilizing an ultralow-power ultralow-voltage envelope detector to obtain the required signal levels, using passive amplification instead of an active low-noise amplifier, and eliminating the voltage regulator removing its power overhead, the transceiver’s input sensitivity has been improved at least by a factor 2 (3 dB) compared to the other previously reported RF-powered transceivers. The proposed transmitter consists of a fast start-up oscillator and an efficient class E power amplifier, which can be externally tuned for different output powers. Fabricated in the TSMC’s 130-nm CMOS process, the measurement results show that the proposed WuRx consuming only 5.7 nW works with input powers as low as −26 dBm, and the proposed transmitter can work with input powers as low as −23 dBm. The WuTx outputs −11 dBm with 51% efficiency at 2.45 GHz using high-Q off-chip components.