Coded Caching in Multi-Rate Wireless Network

Abstract

The network load is increasing due to the spread of content distribution services. Caching is recognized as a technique to reduce a peak network load by prefetching popular contents into memories of users. Coded caching is a new caching approach based on a carefully designed content placement in order to create coded multicasting opportunities. Coded caching schemes in single-rate networks are evaluated by the trade-off between the size of memory and the size of delivered data. Considering the network with multiple transmission rates, it is important how to operate multicast. The multicast needs to use the smallest rate among the available rates for target users. In multi-rate wireless networks, multicast scheduling schemes are evaluated by a throughput and a delay. In this paper, we discuss coded caching in the multi- rate wireless networks. We newly define a throughput and a delay for evaluating the coded caching scheme and propose a new coded caching scheme suitable for these metrics. We compare the proposed coded caching scheme with conventional coded caching schemes.