A Broadband Rectifier With Wide Input Power Dynamic Range Based on Quadrature Coupler for RF Energy Harvesting

In this brief, a rectifier with wide input power dynamic range (WIPDR) is proposed for radio frequency energy harvesting (RFEH). It is composed of a quadrature coupler (QC) and two different sub-rectifiers (<inline-formula> <tex-math notation="LaTeX">${R}$ </tex-math></inline-formula>ectH and <inline-formula> <tex-math notation="LaTeX">${R}$ </tex-math></inline-formula>ectL). Here, <inline-formula> <tex-math notation="LaTeX">${R}$ </tex-math></inline-formula>ectH and <inline-formula> <tex-math notation="LaTeX">${R}$ </tex-math></inline-formula>ectL have different optimal input power levels and they are connected to the two output ports of the QC. In the proposed topology, the reflected power of two sub-rectifiers can be recycled to sub-rectifiers and rectified again due to the feature of the QC. Besides, in each sub-rectifier, three transmission line sections are employed to further extend the dynamic range of input power. Theoretical analysis is carried out. To validate the proposed approach, we design and implement a 2.45 GHz WIPDR rectifier. The measurement results show that the dynamic range of input power for RF-DC power conversion efficiency (PCE) higher than 50% is from 3.7 to 30.7 dBm (27 dB). In addition, its bandwidth (for <inline-formula> <tex-math notation="LaTeX">$S_{11}$ </tex-math></inline-formula><−10 dB) is from 1.74 to 2.8 GHz with a 16 dBm input power <inline-formula> <tex-math notation="LaTeX">$(P_{in})$ </tex-math></inline-formula>. These results indicate that the proposed rectifier not only achieves a broad operating band but also has a WIPDR.