Mobility increases throughput of wireless device-to-device networks with coded caching

The demand for multimedia services in modern networks has experienced exponential growth in recent years and it is expected to dominate the mobile traffic in near future. On the other hand, the link capacity of mobile networks is limited due to the scarce wireless resources. Caching is a popular technique that uses available storage capability of the mobile devices to relieve this traffic tension in high peak hours of network operation. In this paper, we investigate the effect of mobility on a wireless device-to-device (D2D) coded caching architecture. Coded caching is a technique in which library files are split into sub-files and any combination of sub-files can be cached at devices and exchanged between them later. We consider two mobility models for our network architecture and study the effect of mobility on the throughput of the network. We show that, in contrast to the static scenario, by exploiting the mobility in a D2D coded caching network, the coded multi-casting gain and the spatial reuse gain can be attained simultaneously, in terms of the throughput scaling law.