Rate-Power Trade-Off in Solar Cell-based Simultaneous Lightwave Information and Power Transfer Systems

Abstract

The Internet-of-Things (IoT) infrastructure is made of uniquely identifiable wireless-enabled smart devices that use the Internet to communicate with each other as well as people, on a large scale. These IoT devices require power to operate, and to communicate with other smart devices. The optical bands have the capacity to provide power and wireless communication to the IoT devices.

Simultaneous lightwave information and power transmission (SLIPT) is a technology through which information and optical power are received simultaneously by the receiver. SLIPT is made possible by solar cell-based SLIPT receivers. In this thesis, for the first time, the trade-off between the achievable data rate and the harvested power in solar cell-based SLIPT systems is quantified and analysed.

It is known that the amount of power harvested using a solar cell is dependent on its operating voltage. By utilizing a realistic electrical model of the solar cells, an expression for the bandwidth and a lower bound on the data rate of a solar cell receiver as function of the operating voltage is derived. Using the dependency of rate and power on the operating voltage, the rate-power trade-off in solar cell based SLIPT receivers are studied in this thesis.

This work proposes a novel solar cell based SLIPT receiver that includes a DC-DC boost converter, which allows control over the operating voltage of the solar cell. Finally, this thesis proposes an optimization problem to compute the optimum operating voltage for a SLIPT system located indoor where a desired trade-off between the data rate and harvested power can be attained based on the battery state of charge.