Design of Efficient and Compact Ultrawideband Rectifier for Sub-6 GHz WPT/EH

This letter presents an efficient and compact ultrawideband (UWB) rectifier for wireless power transfer (WPT) and energy harvesting (EH) systems. The rectifier utilizes the voltage-doubling topology, which can effectively compress load impedance and facilitate broadband impedance matching. The input impedance matching network (IMN) is achieved using an L-type microstrip branch cascaded with a lumped inductor, which can counteract the capacitive of the diodes and reduce the circuit size. The proposed rectifier was designed and fabricated for verification with a 14.3
$\times $
7.4 mm dimension. The measured results show that the rectifier can provide 197.6% (0.04–6.74 GHz) fractional bandwidth (FBW) with the power conversion efficiency (PCE) exceeding 50% and 196.8% (0.05–6.2 GHz) bandwidth with the PCE exceeding 60% at 22 dBm input power. The peak PCE reaches 74.8% at 1.9 GHz. Compared with traditional UWB rectifiers, the proposed one exhibits the merits of small size, high efficiency, and wider bandwidth.