Outage Minimization for a Fading Wireless Link with Energy Harvesting Transmitter and Receiver

TL;DR

This paper develops and analyzes threshold-based power control policies for minimizing outage probability in energy harvesting wireless links, considering practical constraints like finite batteries, retransmissions, and energy correlation.

Contribution

It introduces optimal threshold-based policies for outage minimization with energy harvesting transmitters and receivers, including finite battery effects and energy correlation.

Findings

Threshold-based policies are optimal under infinite battery capacity.

Battery capacity, energy correlation, and detection costs significantly affect outage performance.

Tradeoff exists between outage probability and average transmission times.

Abstract

This paper studies online power control policies for outage minimization in a fading wireless link with energy harvesting transmitter and receiver. The outage occurs when either the transmitter or the receiver does not have enough energy, or the channel is in outage, where the transmitter only has the channel distribution information. Under infinite battery capacity and without retransmission, we prove that threshold-based power control policies are optimal. We thus propose disjoint/joint threshold-based policies with and without battery state sharing between the transmitter and receiver, respectively. We also analyze the impact of practical receiver detection and processing on the outage performance. When retransmission is considered, policy with linear power levels is adopted to adapt the power thresholds per retransmission. With finite battery capacity, a three dimensional finite state Markov chain is formulated to calculate the optimal parameters and corresponding performance of proposed policies. The energy arrival correlation between the transmitter and receiver is addressed for both finite and infinite battery cases. Numerical results show the impact of battery capacity, energy arrival correlation and detection cost on the outage performance of the proposed policies, as well as the tradeoff between the outage probability and the average transmission times.