An Ultralow-Power RF Wireless Receiver With RF Blocker Energy Recycling for IoT Applications

A wireless RF receiver system suitable for Internet-of-Things (IoT) applications is presented. The system is able to simultaneously harvest energy from out-of-band blockers with normal receiver operation; thus, the battery life for IoT applications can be extended. The system has only a single antenna for simultaneous RF energy harvesting and wireless reception. The receiver is a mixer-first quadrature receiver to tolerate large unavoidable blockers. The system is implemented in 180-nm CMOS technology and operates at a 900-MHz industrial, scientific, and medical band. The receiver gain is 41.5 dB. Operating from a 1-V supply, the receiver core consumes 430 μW . Furthermore, this power can be reduced to 220 μW in the presence of a large blocker (≈0 dBm) by the power provided by the blocker RF energy harvesting where the power conversion efficiency is 30%.