Computation offloading for mobile cloud computing based on wide cross-layer optimization

The aim of this paper is to propose a computation offloading strategy to be used in mobile cloud computing in order to minimize the energy expenditure at the mobile handset necessary to run an application under a delay constraint. The main novelty of the proposed strategy is a wide cross-layer optimization that encompasses the application, MAC and physical layers within a joint framework. We consider a wireless channel affected by fading, with statistics depending on the number of antennas, and we incorporate packet retransmission strategies. The result of the optimization is the joint dynamic allocation of radio resources and offload scheduling that guarantee the stability of the queue of instructions to be executed, in order to minimize the energy consumption at the mobile handset, under a constraint on the average delay. We provide theoretical results proving the existence of an optimal solution of the problem and then we corroborate the theoretical findings with simulation results. The results show for which classes of application and under what kind of channel conditions, computation offloading can provide a significant performance gain.