Delay-Aware Coded Caching for Mobile Users

Cache capacity-delay trade-off is studied for cooperative coded caching among small-cell base stations (SBSs) considering mobile users. First, a delay-aware coded caching policy is introduced, taking into account the popularity of the files and the maximum re-buffering delay constraint, which minimizes the average re-buffering delay of a mobile user under a given cache capacity constraint. Subsequently, a given average re-buffering delay constraint is considered to ensure a certain quality-of-service (QoS) target, and certain files are served by the macro-cell base station (MBS) when the cache capacity of the SBSs is not sufficient to store all the files in the library. A coded caching policy that minimizes the average amount of data served by the MBS is proposed for the latter scenario.