A Dual-Antenna, 263-GHz Energy Harvester in CMOS for Ultra-Miniaturized Platforms with 13.6% RF-to-DC Conversion Efficiency at −8 dBm Input Power

This paper reports a CMOS energy harvester, which operates at so far the highest reported frequency (263 GHz) in order to realize wireless powering of ultra-miniaturized platforms. To maximize the THz-to-DC conversion efficiency, n, at low available radiation power, the harvester not only utilizes a high-speed 22-nm FinFET transistor but also achieves the optimal operating conditions of the device. In specific, the circuit enables self-gate biasing; and through a dual-antenna topology, it drives the transistor drain and gate terminals with both optimal voltage phase difference and power ratio simultaneously and precisely. With a low input power of −8 dBm, the harvester achieves 13.6% measured conversion efficiency and delivers 22 µW to a 1- kΩ load. Without relying on any external component, the harvester chip occupies an area of 0.61 × 0.93 mm 2.