Performance of a Cluster-Based Multihop IoT Network With Battery-Assisted Energy Harvesting

This work investigates a multihop multirelay network in which all nodes are of the battery-assisted (BA) energy harvesting (EH) type, and harvest energy from a power beacon. In each hop, the node with the most harvested energy is selected for relaying and augments the harvested energy with some battery energy. Note that such BA EH nodes are immediately realizable to prolong battery lifetimes. Considering nonlinear EH, analytical expressions are derived for outage probability, throughput, average battery energy consumption, and battery energy efficiency (BEE). It is first shown how the parameters can be chosen to maximize the network throughput. Since unsuccessful relaying that results in outage causes battery energy to be consumed, optimizing the network to minimize the average battery energy consumption or to maximize the node-level BEE is well motivated. We show that the judicious selection of the EH duration can minimize average battery energy consumption while achieving the target throughput requirement. Moreover, a joint optimal choice of EH duration, hop count, and target information rate is shown to maximize overall BEE. Monte Carlo simulations validate the accuracy of the derived expressions.