Design of High-Efficiency Broadband Rectifier With Harmonic Control for Wireless Power Transfer and Energy Harvesting

In this letter, a novel methodology for designing a broadband rectifier with high efficiency and an extended dynamic range of input power is proposed for wireless power transfer (WPT) and energy harvesting (EH). The proposed structure consists of two main networks. The first one reduces diode impedance variation with only two transmission lines (TLINs). The second network deploys a synthesized three-stage, low-pass matching network (MN) to match the reduced-variation fundamental impedance to the source of 50 omega. The harmonic impedances in the stopband of this low-pass MN is manipulated to reshape the diode-across current and voltage following the Class-C or Class-R standard waveforms for power conversion efficiency (PCE) enhancement. For validation, a HSMS2860-based rectifier prototype is tested showing a bandwidth of 43.5% from 1.8 to 2.8 GHz with 72%-above PCE at an input power of 14 dBm. In addition, the PCE of over 70% is achieved across a bandwidth of 48.9% (1.7-2.8 GHz) with the highest of 82.5% at 12 dBm while the measured PCE can remain above 47% within the same bandwidth at a low input power of 0 dBm. Furthermore, the proposed rectifier has a comparative size of 46 mm x 32 mm.