A General Utility Optimization Framework for Energy-Harvesting-Based Wireless Communications

In the near future, wireless communication systems are expected to achieve more cost-efficient and sustainable operations by replacing conventional fixed power supplies such as batteries with energy harvesting devices, which could provide electric energy from renewable energy sources (e.g., solar and wind). Such EH power supplies, however, are random and unstable in nature, and as a result impose new challenges on reliable communication design and have triggered substantial research interest in EH-based wireless communications. Building on existing works, in this article, we develop a general optimization framework to maximize the utility of EH wireless communication systems. Our framework encapsulates a variety of design problems, such as throughput maximization and outage probability minimization in single-user and multiuser setups, and provides useful guidelines to the practical design of general EH-based communication systems with different assumptions regarding the knowledge of time-varying wireless channels and EH rates at the transmitters.