Research on Cache Strategy of Supporting D2D Communication Based on Recommendation Mechanism

Abstract

In D2D wireless cache network, a good cache strategy is very important, but the current cache strategy has the problems of low cache hit rate and high base station cost. Aiming at this problem, this paper proposes a smart base station cache strategy based on recommendation mechanism. Through the Q-learning algorithm to learn user mobility and file popularity information, a base station cache strategy with the goal of minimizing long-term base station cost is obtained. How to formulate the base station cache strategy and set the recommendation mechanism under different user movement scenarios in the cellular network. The simulation results show that the lower the user’s mobility rate is, the smaller the optimal recommendation strength is. In the four user mobility scenarios in the simulation, the proposed cache strategy reduces the core network cost by up to 22.4% compared with the greedy cache, and it is reduced by up to 18.6% recommended strategy.