Broadband RCN-based RF-rectifier with a large range of power for harvesting ambient wireless energy

Abstract

In this paper, a broadband RF-rectifier with a wide scale of RF input power levels, using FR-4 substrate, is proposed. A wideband resistance compression network (RCN) is applied to achieve the unique RF-rectifier design approach. The method improves the matching performance of the circuit over a broader range of the available input RF signals and frequency. The RF-rectifier circuit is configured in two sections. The two sections are configured using a modified L-section matching network (MN) through a series impedance transformer (ITx). A wideband RCN integrates the two RF-rectifier segments to a 50 Ω transmission line (TL). The design provides a wider span of accessible RF power from −15 to 15 dBm via a 2 kΩ load terminal. The proposed RF-rectifier achieved a simulated and measured fractional percentage bandwidth (FBW) of 38.5% and 38% from 1.780 to 2.620 GHz and 1.780 to 2.610 GHz, respectively. The maximum measured RF-to-DC PCE and output DC voltage (Vdc) realized by the proposed RF harvester are 75.5% and 3.2 V, respectively. The design also reached a high PCE of 88.25% and 15.10%, respectively, from the quad-tone signals at 10 and −20 dBm RF input power. The proposed RF-rectifier’s ambient evaluation produces a Vdc of 0.322 V and also activated a low-power bq25504-674 evaluation module (EVM) at 0.682 V.