Cache- and Energy Harvesting-Enabled D2D Cellular Network: Modeling, Analysis and Optimization

With the improvement of quality of service requirement and the increase of energy expenditure, integrating caching and energy harvesting (EH) to device-to-device (D2D) communication is a prospective but challenging research. In this paper, we focus on investigating the network performance with stochastic geometry for cache- and EH-enabled D2D cellular network, in which each mobile user (MU) can cache contents from the base station and be charged through EH. Specifically, taking into account the knowledge of the energy states and the requested contents, along with the randomness of content caching, each MU can fetch its requested file via three modes, i.e., self-satisfied, D2D communication and cellular downlink communication. In view of this observation, stochastic geometry is applied to analyze the system transmission model, and from which the content delivery strategies are designed, as well as the cache hit probability and successful transmission probability are characterized under three modes, respectively. Based on the analyzed results, two probabilistic caching strategies with different objectives are further designed to maximize the cache hit probability and the network successful offloading probability. Finally, comprehensive simulations are provided to analyze the effect of different parameters on network performance and verify the superiority of the proposed caching strategies.