RF-Powered Transceiver With an Energy- and Spectral-Efficient IF-Based Quadrature

Abstract

This study introduces a 5.8 GHz RF-powered trans- ceiver that includes a transmitte r using an IF-based quadrature backscattering (IFQB) technique . The IFQB transmitter can pro- duce a quadrature modulated signal without active RF circuits, such as PLL, local generation, and local distribution circuits. Thus, the IFQB technique can significantly reduce the power consump- tion while achieving denser constellations by the quadrature mod- ulation. The RF-powered transceiver consists of the IFQB trans- mitter, an OOK receiver, and a power management unit (PMU) for RF powering. The transmitter and receiver operate und er a 0.6 V power supply provided by the PMU to further reduce the power consumption. We fabricated a prototype RF-powered trans- ceiver using a 65 nm Si CMOS process to confirm the validit yo f the proposed technique. During the measurements, the transmitter achieved 2.5 Mb/s with a 32-QAM modulation while consuming 113 µW. In addition, a wireless temperature sensing demonstration was conducted using the prototype sensor node with the presented RF-powered transceiver.