中继选择和队列稳定动态能量优化策略  

Dynamic Energy Optimization Strategy Based on Relay Selection and Queue Stability

作　　者：陈澈 郑艺峰 杨敬民 杨立伟 张文杰 CHEN Che;ZHENG Yifeng;YANG Jingmin;YANG Liwei;ZHANG Wenjie(College of Computer Science,Minnan Normal University,Zhangzhou,Fujian 363000,China;Key Laboratory of Data Science and Intelligence Application,Fujian Province University,Zhangzhou,Fujian 363000,China;College of Electronic Engineering,Taipei University of Technology,Taipei 106344,China;College of Information and Electrical Engineering,China Agricultural University,Beijing 100083,China)

机构地区：[1]闽南师范大学计算机学院,福建漳州363000 [2]数据科学与智能应用福建省高校重点实验室,福建漳州363000 [3]台北科技大学电子工程系,中国台北106344 [4]中国农业大学信息与电气工程学院,北京100083

出　　处：《计算机科学》2023年第S01期673-680,共8页Computer Science

基　　金：国家自然科学基金(62141602);福建省自然科学基金(2021J011002,2021J011004,2020J01813)。

摘　　要：中继辅助移动边缘计算(Mobile Edge Computing,MEC)是近年来兴起的一种很有前景的方式,它可以提高5G网络和物联网(Internet of Things,IoT)等低功耗网络的资源利用率和数据处理能力。然而,设计中继选择和计算卸载策略以提高队列稳定系统的能量效率仍然是一个挑战。为解决中继辅助移动边缘计算系统中的能耗优化问题,在任务缓冲队列稳定性约束下,建立混合整数非线性随机优化模型,最小化系统的长期平均能耗。该问题被分解为中继节点选择和中继卸载决策两个阶段进行求解。在中继选择阶段,通过设置权重参数V 1最小化传输能耗和缓冲队列长度的加权和来确定中继节点;在卸载决策阶段,应用李雅普诺夫方法将随机优化问题转化为确定性优化问题,在保持任务缓冲队列稳定的条件下,得到最优中继计算频率、最优中继传输功率,以及最优远程节点计算频率的理论表达式。仿真结果表明,该能量优化策略能够在缓冲队列稳定约束下有效降低系统的长期平均能耗,并收敛到穷举搜索的最优解,同时可通过调整算法中参数V 1和V 2的来取值改变能耗和等待时长的权重。Relay-assisted mobile edge computing(MEC)has recently emerged as a promising paradigm to enhance resource utilization and data processing capability of low-power networks,such as 5G networks and Internet of things(IoT).Nevertheless,the design of relay selection and computation offloading policies to improve the energy efficiency for queue stability system remains challenging.In order to solve the energy consumption optimization problem in relay-assisted MEC system,a mixed integer nonli-near stochastic optimization model is established,with the objective of minimizing the long-term average energy consumption,subject to a task buffer stability constraint.The problem is solved by decomposing into two stages:relay selection and relay offloa-ding decision.In relay selection stage,the relay node is determined by setting a weighted parameter V 1 to minimize the weighted sum of transmission energy consumption and buffer queue length.In offloading decision stage,the stochastic optimization is converted to a deterministic optimization problem based on Lyapunov optimization method.Specifically,at each time slot,the theore-tical expressions of optimal relay calculation frequency,relay transmission power and remote calculation frequency are obtained under the constraint of task buffer queue stability.Simulation results show that the energy optimization strategy can effectively reduce the long-term average energy consumption under the constraint of buffer queue stability,and converge to the optimal solution obtained by exhaustive searching.Besides,the weight of energy consumption and waiting time can be changed by adjusting the values of parameters V 1 and V 2 in algorithm.

关 键 词：移动边缘计算 中继选择 缓冲队列 卸载决策 能量优化 

分 类 号：TP3-05[自动化与计算机技术—计算机科学与技术]