The unprecedented growth of internet contents, specially social media, makes a challenge to the load of cellular networks. Latency is one of the most important metrics at end-users. To this end, we propose a resource allocation (RA) algorithm to design both caching and delivery policies with the aim of minimizing total latency of mobile users (MUs), where in the caching phase, the content placement is investigated and in the delivery phase, we allocate radio resources (i.e., transmit powers and subcarriers) in a multi-cell orthogonal frequency division multiple access (OFDMA)-based network communicating with a data center via backhaul links.
In order to achieve an efficient caching policy, we propose an optimization problem to minimize the latency of MUs subject to maximum delivery deadline, maximum allowable transmit power of each base station (BS) and data center, and exclusive subcarrier assignment constraints. Hence, we devise an iterative algorithm to solve the main optimization problem and prove that the proposed approach converges to a near-optimal solution, when the number of iterations increases. Moreover, simulation results illustrate that devising the transmission-aware caching policy can significantly improve the performance, compared to the conventional proactive caching policies which are only based on the popularity of contents and the storage capacity of BSs.

Keywords: Caching policy, delivery policy, OFDMA, resource allocation, latency

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