On Wirelessly Powered Communications with Short Packets

TL;DR

This paper analyzes wireless-powered communication systems with short packets, focusing on finite-length information theory to optimize energy transfer and data transmission under practical constraints.

Contribution

It introduces a finite-length information theory framework for wireless-powered communications, deriving closed-form expressions for optimal transmit power and system performance metrics.

Findings

Power control significantly improves achievable rates.

Closed-form expressions for asymptotically optimal transmit power.

Insights into system behavior based on key parameters.

Abstract

Wireless-powered communications will entail short packets due to naturally small payloads, low latency requirements and/or insufficient energy resources to support longer transmissions. In this paper, a wireless-powered communication system is investigated where an energy harvesting transmitter, charged by a power beacon via wireless energy transfer, attempts to communicate with a receiver over a noisy channel. Leveraging the framework of finite-length information theory, the system performance is analyzed using metrics such as the energy supply probability at the transmitter, and the achievable rate at the receiver. The analysis yields useful insights into the system behavior in terms of key parameters such as the harvest blocklength, the transmit blocklength, the average harvested power and the transmit power. Closed-form expressions are derived for the asymptotically optimal transmit power. Numerical results suggest that power control is essential for improving the achievable rate of the system in the finite blocklength regime.