Impact of 2-ASK Back-Scattering Modulation on Harvesting Efficiency for 5.8 GHz Batteryless Transponder based on a Rectenna Array

This paper analyzes the interaction between the back-scattering modulator and the energy harvesting efficiency in a IoT node, with the aim to increase the available communication time slot by overlapping the harvesting and the back-scattering operations. Experimental results shown that during the back-scattering the harvesting efficiency is reduced to 49% with respect the case of modulator set to off, i.e. 71%, but the operational duty cycle is increased of a factor three if the harvesting process continues during the back-scattering modulation. Thus determining an operational advantage in battery-less transponder communications.