High-Efficient Rectifier With Extended Input Power Range Based on Self-Tuning Impedance Matching

摘要

In this letter, a microwave rectifier with a wide input power range is presented by proposing a self-tuning impedance matching (STIM). The STIM consists of a varactor reversely biased by the output voltage of the rectifier to compensate the variation of the input impedance caused by the input power, so that impedance matching is obtained over a wider input power range. For validation, the proposed rectifier at 2.4 GHz was designed and implemented. The experimental results show that the RF-dc power conversion efficiency maintains over 50% and 70% within the input power ranges of 2.5–25.5 dBm and 11–24.5 dBm, respectively. Compared with the counterpart without the STIM, an improvement of 7.2 dB in terms of the input power range when the reflection coefficient is less than −10 dB was successfully demonstrated.