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It is widely recognized that caching is an indispensable technology for thenext generation mobile content delivery networks (CDNs).In particular, caching atmobile base stations (BS) can help to reduce the backhaul traffic and improve userscontent access experience.The recently proposed Opportunistic wireless ContentDelivery Network (OwCDN) is a promising new paradigm of mobile CDN.It aims toexploit the redundant capacity in cellular access networks forsecondary content delivery service, such that the utilization efficiency of the cellularnetwork can be improved. This paper studies novel BS caching schemes tailored for OwCDN.This thesisfirst presents a brief review of traditional caching policies and discussesnew challenges for BS caching in OwCDN.An explicit BS caching scheme isthen proposed.Unlike traditional "transparent" caching schemes, our caching schemeis "explicit" in a way that users content request is constrained to the alreadycached content at the local BS.Second, we study the problem of pro-active andexplicit BS caching with user mobility awareness.The problem is formulated as acombinatorial optimization problem.Four heuristic algorithms are proposed to solvethe problem.The performance of these algorithms is compared and discussed.Third,the problem of explicit BS caching is further refined by considering the fairnessconstraint among users.A heuristic algorithm is proposed to solve the problem.In theabove two problems, the impacts of storage size and redundant capacity on theeffectiveness of BS caching are thoroughly studied via simulations.Our studies findthat significant performance gains can be obtained when caching policies can adapt tothe size of caching storage, the amount of redundant capacity, and the user mobilitypatterns.We conclude that explicit BS caching is a promising new paradigm of BScaching in next generation mobile communication networks.