Cooperative wireless edge caching with relay selection

Relay selection is a simple yet effective means to improve the reliability and coverage of wireless cooperative networks. However, it suffers from inefficient use of the available bandwidth resources. This paper introduces the use of content caching at relays in order to tackle this problem and improve the performance of relay selection. Three cache placement schemes are considered: one based on the  most popular files, a uniform based caching and a hybrid scheme of the two. We analytically derive their outage performance as well as their diversity order and coding gain. Numerical results demonstrate the substantial performance gains of these schemes over the traditional optimal relay selection approach without caching capabilities.