Uplink power optimized in-network content caching for HetNets

Video upload/download involving applications are among the most popular applications for mobile users. Meanwhile they cause wireless networks to run close to their capacity limits. In addition, uploading or downloading content put pressure on the limited battery capacity of mobile devices. Given the fact that popular contents are acquired by a large number of users at different times, it is practical to fetch those contents from the content source and store in-network. This is known as in-network caching. In the literature, latency and transport energy minimization aware in-network caching has been studied widely. However, uplink power optimization which aims prolonging User Equipment (UE) lifetime have not been considered yet. To address this problem, we cache contents at wireless relays of a Heterogeneous Network (HetNet) and propose two Integer Linear Programming (ILP) models to optimize uplink power. The first ILP model, namely Minimize Uplink Power (minUP). MinUP aims to minimize uplink power when relays and their contents are known. The second ILP-based scheme is called Minimize Uplink Power and Relay Cost (minUPREC). MinUPREC jointly minimizes uplink energy and relay deployment cost. We have shown that minUPREC significantly minimizes the uplink energy incurred by UEs while minUP consumes lower caching.