Communication and Computation Cooperation in Wireless Network for Mobile Edge Computing

The advantages of mobile edge computing (MEC) in lower energy consumption, improved bandwidth and reduced delay have attracted extensive studies. We consider a multiple smart wearable devices (SWDs) single smart mobile device (SMD) MEC system where the computation-intensive tasks can be offloaded to SMD and MEC server to improve resources utilization in this paper. To further minimize the energy consumption and satisfy the delay constraints of SWDs, SMD cooperation is introduced and we jointly optimize two-tier computation and communication resources in this system to achieve our objective. The formulated problem is a non-convex optimization problem where we design an efficient iterative algorithm by integrating the block coordinate descent and convex optimization techniques together. The proposed algorithm ensures convergence to a suboptimal solution based on the properties of convex optimization problem. In particular, the original non-convex optimization problem is decomposed into two convex optimization subproblems. Furthermore, we simplify the first subproblem using Lagrange method which is transformed into solving a set of non-linear equations. The extensive simulation results indicate that the proposed algorithm by jointly optimizing two-tier computation and communication resources can reduce energy consumption compared with other baseline methods. The solution of proposed algorithm is close to the optimal solution and can be generated in a shorter time.