Efficient Algorithms for Power Maximization in the Vector Model for Wireless Energy Transfer

Rapid technological advances in the domain of Wireless Power Transfer (WPT) pave the way for novel methods for power management in systems of wireless devices and recent research works have already started considering algorithmic solutions for tackling emerging problems. However, those works are limited by the system modelling, and more specifically the one-dimensional abstraction suggested by Friis formula for the power received by one antenna under idealized conditions given another antenna some distance away. Different to those works, we use a model which arises naturally from fundamental properties of the superposition of energy fields. This model has been shown to be more realistic than other one-dimensional models that have been used in the past and can capture superadditive and cancellation effects. Under this model, we define two new interesting problems for configuring the wireless power transmitters so as to maximize the total power in the system and we prove that the first problem can be solved in polynomial time. We present a distributed solution that runs in pseudo-polynomial time and uses various knowledge levels and we provide theoretical performance guarantees. Finally, we design three heuristics for the second problem and evaluate them experimentally.