Joint Computation Offloading and Resource Optimization for Minimizing Network-Wide Energy Consumption in Ultradense MEC Networks

In this article, the orthogonal frequency-division multiple access (OFDMA) integrated with frequency spectrum (band) partitioning and equal bandwidth allocation is first introduced to mitigate the complicated, severe, and average network interferences in ultradense mobile edge computing (MEC) networks. Then, under such OFDMA, the system energy consumed by all users [mobile devices (MDs)] and base stations (BSs) is minimized to reduce the huge energy consumed by ultradense small BSs (SBSs) and prolong the standby time of MDs, jointly optimizing the spectrum partitioning factor, local and remote computation capacities, local power, and binary offloading decision. According to the coupling form of optimization parameters in the formulated problem, this problem is first cut into a joint power control and resource (frequency spectrum) partitioning (PCRP) subproblem, a joint user association, and a computation capacity optimization (UACCO) subproblem. Then, we try to design an effective iteration algorithm to attain the solutions to these problems using convex optimization methods. As for this algorithm, we give some detailed convergence, computation complexity, and simulation analyses. The simulation results show that it may achieve a guaranteed offloading performance and lower energy consumption than other existing algorithms.