School of Information Engineering, Minzu University of China, Beijing 100081, China.
School of Computer and Information Technology, Beijing Jiaotong University, Beijing 100044, China.
Sensors (Basel). 2019 Mar 22;19(6):1422. doi: 10.3390/s19061422.
The fog radio access network (F-RAN) equipped with enhanced remote radio heads (eRRHs), which can pre-store some requested files in the edge cache and support mobile edge computing (MEC). To guarantee the quality-of-service (QoS) and energy efficiency of F-RAN, a proper content caching strategy is necessary to avoid coarse content storing locally in the cache or frequent fetching from a centralized baseband signal processing unit (BBU) pool via backhauls. In this paper we investigate the relationships among eRRH/terminal activities and content requesting in F-RANs, and propose an edge content caching strategy for eRRHs by mining out mobile network behavior information. Especially, to attain the inference for appropriate content caching, we establish a pre-mapping containing content preference information and geographical influence by an efficient non-uniformed accelerated matrix completion algorithm. The energy consumption analysis is given in order to discuss the energy saving properties of the proposed edge content caching strategy. Simulation results demonstrate our theoretical analysis on the inference validity of the pre-mapping construction method in static and dynamic cases, and show the energy efficiency achieved by the proposed edge content pre-caching strategy.
雾无线接入网（F-RAN）配备了增强型远程无线电头（eRRH），可以在边缘缓存中预存储一些请求的文件，并支持移动边缘计算（MEC）。为了保证 F-RAN 的服务质量（QoS）和能效，需要采用适当的内容缓存策略，以避免在缓存中本地存储粗粒度内容，或通过回程频繁地从集中基带信号处理单元（BBU）池中获取内容。本文研究了 F-RAN 中 eRRH/终端活动与内容请求之间的关系，并通过挖掘移动网络行为信息，为 eRRH 提出了一种边缘内容缓存策略。特别是，为了实现适当的内容缓存推断，我们通过高效的非均匀加速矩阵完成算法建立了包含内容偏好信息和地理影响的预映射。给出了能量消耗分析，以讨论所提出的边缘内容缓存策略的节能特性。仿真结果验证了我们在静态和动态情况下对预映射构建方法推断有效性的理论分析，并展示了所提出的边缘内容预缓存策略的能量效率。
