Development of High-Power Charge Pump Rectifier for Microwave Wireless Power Transmission
Koki Miwatashi, Takashi Hirakawa, Naoki Shinohara, Tomohiko Mitani
Abstract
This study theoretically and experimentally indicates that a charge pump rectifier for low-power rectifiers such as RF-ID can be applied to high-power rectifiers and can attain the same level of RF-dc conversion efficiency and twice as high power rectification as the single-shunt rectifiers. A high-power rectifier is primarily a single-shunt rectifier, and a charge pump rectifier that applies twice the output voltage is used in low-power applications such as RF-ID. We aim to enhance the power of charge pump rectifiers by focusing on their characteristics. A fabricated 5.8 GHz charge pump rectifier achieved an RF-dc conversion efficiency of 70.8% at an input power of 8.0 W and a load resistance of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$150\,\Omega$</tex-math></inline-formula> . This result is also the highest efficiency for 39 dBm rectifiers in the 5.8 GHz band. Compared to a single-shunt rectifier with the same diode, the charge pump rectifier generated twice the input power and efficiency difference of 2.9% at the maximum input power. These results indicate that the charge pump rectifier has an advantage over the single-shunt rectifier in high-power rectifiers.