Incentive Mechanism Design for Wireless Energy Transfer in IoT

Wireless energy transfer has been recently viewed as a promising solution to extend the operation time of wireless devices (e.g., sensors) for Internet of Things (IoT) system. In this paper, we formulate a business model and use the contract approach to study the energy transfer and pricing issue in IoT system, where the energy access point (EAP) gains revenue from providing wireless energy transfer to the various devices in the IoT system. Specifically, the EAP designs and offers a set of contract items in the form of transmit power and the corresponding payment. Then each IoT device will choose a contract item to maximize its payoff based on the private information (i.e., the type). Furthermore, we first derive the necessary and sufficient condition to make the contract feasible, i.e., satisfying incentive compatibility (IC) and individual rationality (IR) constraints, and then we analytically derive the optimal and feasible contract that maximizes the profit of the EAP. The numerical results further reveal that the EAP tends to exclude some IoT device from enjoying wireless power transfer service to maximize its profit. And the proposed power-based price differentiation can increase EAP's profit up to 36.6% compared with the no-differentiation case.