Optimal Throughput-Outage Analysis of Cache-Aided Wireless Multi-Hop D2D Networks
Optimal Throughput-Outage Analysis of Cache-Aided Wireless Multi-Hop D2D Networks
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DOI：
10.1109/tcomm.2020.3045787
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发表时间：
2020-05
影响因子：
8.3
通讯作者：
Ming-Chun Lee;Mingyue Ji;A. Molisch
中科院分区：
文献类型：
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作者：
Ming-Chun Lee;Mingyue Ji;A. Molisch
缓存辅助的无线设备到设备(D2D)网络在视频分发方面表现出比传统分发方法更有希望的性能改进；因此，了解此类网络的基本可伸缩行为非常重要。然而，现有的多跳网络的标度律即使在Zipf流行度分布的情况下也不是最优的(上下限之间的差距不是常量)；此外，对于Mandelbrot-Zipf(MZipf)流行度分布的更实际情况，没有针对此类网络的标度律结果。因此，我们研究了采用多跳通信的缓存辅助无线D2D网络的吞吐量-中断性能，其中文件请求和用户的MZipf热度分布按泊松过程分布。提出了一种可实现的内容缓存和分发方案，并对其性能进行了分析。通过证明可实现的性能紧靠所提出的外界，我们得到了最优标度律。由于Zipf分布是MZipf分布的特例，因此还得到了考虑Zipf流行分布的网络的最优标度律，填补了文献中的空白。
Cache-aided wireless device-to-device (D2D) networks have demonstrated more promising performance improvement for video distribution than conventional distribution methods; thus, understanding the fundamental scaling behavior of such networks is highly important. However, the existing scaling laws for multi-hop networks are not optimal even in the case of Zipf popularity distributions (gaps between upper and lower bounds are not constants); furthermore, there are no scaling law results for such networks for the more practical case of a Mandelbrot-Zipf (MZipf) popularity distribution. We thus in this work investigate the throughput-outage performance for cache-aided wireless D2D networks adopting multi-hop communications, with the MZipf popularity distribution for file requests and users distributed according to Poisson point process. We propose an achievable content caching and delivery scheme, and then analyze its performance. We obtain the optimal scaling law by showing that the achievable performance is tight to the proposed outer bound. Since the Zipf distribution is a special case of the MZipf distribution, the optimal scaling law for the networks considering the Zipf popularity distribution is also obtained, which closes the gap in literature.