A Novel Structure of Compact and High-Efficiency Dual-Band Rectifier With Low Complexity for Wireless Power Transfer

Abstract

A novel methodology is presented for designing compact and high-efficiency dual-band (DB) rectifier with low insertion loss and complexity. The proposed network implements an opposite order of fundamental matching and harmonic control, as compared to the conventional approaches. Specifically, a typical T-type DB fundamental matching network with closed-form formulas is first used to match directly the diode impedance to the 50Ω standard load. As analyzed, this matching circuit consistently generate a perfect DB matching due to the frequency-dependent diode impedance without any additional impedance tuning methods, yielding a low design complexity. Then, a DB harmonic control mechanism is provided by combination of a DB resonator and a 50Ω tuning series line, which can yield precise class-R harmonic termination of second and third harmonics with only a total of three transmission lines leading a low insertion loss. A rectifier is designed, simulated and measured at two target frequencies of 2.45 and 5.8 GHz for verification. The measured results show a peak PCE of 80.6% at 2.33 GHz and 73.1% at 5.65 GHz while having a compact size of 4.6×3.1 cm2, indicating achievement of a superior performance with a simplicity of the design process to the other similar designs.