RF Energy Harvester for Wireless and Battery-Free Accelerometers Based on All Fabric Dipole Array

This paper introduces an RF energy harvester integrated into a fabric knee support sleeve to enable wireless and battery-free accelerometers for motion capture. The harvester comprises an all-fabric dipole rectenna array consisting of three embroidered elements operating in the UHF band. All rectennas are connected to a flexible boost converter circuit to provide an output voltage of 1.8 V at 1 m separation distance from the transmitter, which is sufficient to power low-power accelerometers. Results also indicate that the time taken to activate the boost converter increases by a factor of 2.22 in the presence of the human body.