Efficient Energy Management Policies for Networks with Energy Harvesting Sensor Nodes

TL;DR

This paper develops and compares energy management and MAC policies for energy harvesting sensor networks, optimizing throughput and delay, with practical suboptimal solutions for real-world implementation.

Contribution

It introduces throughput optimal and delay-minimizing policies for single nodes and extends these to efficient MAC protocols for sensor networks.

Findings

Identified a greedy policy that is throughput optimal in low SNR and minimizes delay.

Developed policies that maximize data queue stability and minimize mean delay.

Compared performance of various practical suboptimal policies.

Abstract

We study sensor networks with energy harvesting nodes. The generated energy at a node can be stored in a buffer. A sensor node periodically senses a random field and generates a packet. These packets are stored in a queue and transmitted using the energy available at that time at the node. For such networks we develop efficient energy management policies. First, for a single node, we obtain policies that are throughput optimal, i.e., the data queue stays stable for the largest possible data rate. Next we obtain energy management policies which minimize the mean delay in the queue. We also compare performance of several easily implementable suboptimal policies. A greedy policy is identified which, in low SNR regime, is throughput optimal and also minimizes mean delay. Next using the results for a single node, we develop efficient MAC policies.