A General Efficiency Enhancement Method for Compact Broadband Rectifiers

This paper presents a general efficiency enhancement method for compact broadband rectifiers. First, a simple LCR model is employed to characterize the frequency-dependent parasitic effects of Schottky barrier diodes (SBDs) in broadband. Subsequently, based on the LCR model, a compact rectifier circuit configuration is proposed to minimize impedance mismatch in broadband, thereby significantly improving the rectification efficiency. To validate the proposed approach, two representative rectifier prototypes are designed, fabricated, and measured. The measured results show that Rectifier I achieves a power conversion efficiency (PCE) exceeding 70% across 0.5–2.5 GHz under 20 dBm input power with a\,1000Ωload, while Rectifier II attains a PCE above 64% from 1.1 to 5.4 GHz under 10 dBm input power with the same load. Compared with state-of-the-art designs, the proposed rectifiers exhibit superior PCE performance while achieving a fractional bandwidth (FBW) exceeding 100%. Notably, the proposed efficiency enhancement technique is suitable for most broadband rectifier designs, such as diverse rectifier topologies, SBD types, input power levels, and load conditions.