Offloading efficiency optimization for uplink mobile edge computing based on NOMA and user collaboration
To meet the demand of large-scale computing tasks and the challenge of limited transmission resources and serious channel fading,we propose a non-orthogonal multiple access(NOMA)and user cooperation assisted uplink mobile edge computing(MEC)offloading scheme.In this scheme,the user offloads computing tasks to the MEC server through NOMA to improve spectrum efficiency,and the local user helps the remote user with offloading to reduce the impact of outages on computing offloading.To achieve the best tradeoff between unloading quantity and energy consumption,the offloading efficiency is defined as the ratio of the amount of successfully offloaded data to the energy consumed by users.A joint optimization problem is established to maximize the offloading efficiency by adjusting the offloading time and power allocation.To solve this problem,a closed-form expression of the outage probability of a pair of users is derived.Then,the nonconvex problem is transformed into a relaxed problem and solved by continuous convex approximation.The simulation analyzes the outage performance of the system,and the results demonstrate that the proposed method can achieve higher offloading efficiency compared with other schemes.
mobile edge computing(MEC)non-orthogonal multiple access(NOMA)user cooperationcomputational offloading
国家科技期刊平台
NSTL
万方数据
