Abstract

This paper investigates a cache-aided mobile edge computing (MEC) network, where the source offloads the computation task to multiple destinations with computation capacity, with the help of a cache-aided relay. For the proposed cache-aided MEC networks, two destination selection criteria have been proposed to maximize the computation capacity of the selected destination, the channel gain of relay link and the channel gain of direct link, respectively. Similarly, three destination selection criteria have been proposed for the cache-free MEC networks based on the computation capacities of destinations and the channel gains of transmission links, respectively. To evaluate the system performance regarding the latency constraint, we provide the outage probability for the proposed network which is defined based on the transmission-plus-computation time. Our analysis suggests that caching can significantly alleviate the impact of increasing the size of computation task, since only half of the transmission time of cache-free network is required. However, the cache-aided network can not fully exploit the signal from both direct and relay links, thus the improvement by caching is less significant in the high signal-to-noise ratio (SNR) region, compared with the cache-free network employing the destination with maximal channel gain of direct link. Numerical results are given to validate our analysis.

中文翻译：

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用于B5G无线通信网络的缓存辅助移动边缘计算

摘要

本文研究了一种高速缓存辅助的移动边缘计算（MEC）网络，其中源借助高速缓存辅助的中继将计算任务分流到具有计算能力的多个目标。对于所提出的高速缓存辅助MEC网络，已经提出了两个目的地选择标准以最大化所选择目的地的计算能力，分别是中继链路的信道增益和直接链路的信道增益。类似地，已经分别基于目的地的计算能力和传输链路的信道增益针对无缓存的MEC网络提出了三种目的地选择标准。为了评估有关等待时间约束的系统性能，我们提供了基于传输加计算时间定义的建议网络的中断概率。我们的分析表明，缓存可以极大地减轻增加计算任务大小的影响，因为仅需要无缓存网络传输时间的一半。但是，高速缓存辅助网络无法充分利用来自直接链路和中继链路的信号，因此，与使用无高速缓存的网络相比，通过高速缓存进行的改进在高信噪比（SNR）区域中的意义不大。具有最大直接链路信道增益的目的地。数值结果证明了我们的分析。因此，与采用直接链路的最大通道增益的目标的无缓存网络相比，在高信噪比（SNR）区域中，通过缓存进行的改进意义不大。数值结果证明了我们的分析。因此，与采用直接链路的最大通道增益的目标的无缓存网络相比，在高信噪比（SNR）区域中，通过缓存进行的改进意义不大。数值结果证明了我们的分析。