High-efficiency rectifier using composite right-/left-handed transmission line

A novel high-efficiency rectifier using a composite right-/left-handed (CRLH) transmission line (TL) is proposed for 900 MHz wireless power transmission applications. The open-ended CRLH TL stub replaces the bandpass filter (BPF) of a conventional rectifier and has a small size as compared to the traditional BPF. The open-ended CRLH TL stub is designed to suppress the second and third harmonics and to match the fundamental frequency to 50 Ω impedance. The maximum RF-to-DC conversion efficiency of the proposed rectifier is 69.9% at an input power of 50 mW and a load of 1.8 kΩ. A design procedure based on the phase response of a CRLH TL is presented and validated by simulated and measurement results.