A Highly Efficient Design of 2.45/5.8-GHz Dual-Band Class-F Shunt-Diode Rectifier for Wireless Power Transmission

In this letter, a dual-band (DB) class-F harmonic termination structure is proposed for designing a DB high-efficiency rectifier at two highly spaced separate frequency bands, that is, 2.45 and 5.8 GHz for wireless power transmission (WPT). The structure uses seven cascaded transmission lines (TLINs) to manipulate accurately the second and third harmonics of two design frequencies for reshaping class-F diode waveforms. The TLIN parameters are analyzed, and closed-form design equations are derived. The HSMS2860-based rectifier shows that the measured highest power conversion efficiency (PCE) is attained at 77.7% and 71.3% for 2.31 and 5.47 GHz with an input power of 13 and 12.5 dBm, respectively. Moreover, 50%-over PCE is maintained within a wide dynamic range of 18 dB at low frequency and 11.5 dB at high frequency. Compared to the existing designs, the proposed rectifier exhibits a superior PCE while having a compact size of 6
$\times $
2.5 mm. To our best knowledge, with the deployment of such a DB harmonic termination network incorporated with a DB fundamental matching network, PCE is recorded highest at these frequency bands.