Share communication and energy resources for mobile cloud computing: An optimal cooperative contract approach

In this paper, we propose a cooperative contract approach to study the optimal energy-communication resource sharing for mobile cloud computing between energy-poor mobile devices and data-poor mobile devices. Specifically, an energy-poor mobile device with an energy harvesting module harvests energy from a data-poor mobile device through power splitting policy. In reciprocity, the energy-poor device will help relay the data-poor mobile device's computation task with part of the harvested energy. Firstly, we formulate an optimization model for designing of the optimal cooperative contract, and find that it is a multivariable non-convex optimization problem. Then, we transform it into a solvable convex optimization problem and derive the close-form expressions of the optimal harvest-energy allocation factor, the optimal power splitting factor, and the optimal transmission power through theoretical analysis. Finally, numerical results prove the unification between theoretical analysis and simulation results. Meanwhile, it is shown that our scheme reduces both of the energy consumption and data usage for resource-constrained mobile devices in utilizing mobile cloud computing.