A Cluster-Based Hybrid Access Strategy Using Non-cooperative Game Theory for Ultra-dense HetNet

The data traffic is exploding dramatically, 1000-fold data traffic increase is expected in this decade. Ultra-dense heterogeneous network (HetNet) is considered as a promising track to address this challenge. In order to mitigate the severe interference between the dense deployed small cells and improve the cell edge users' performances, cluster-based spectrum allocation and coordinated multi-point transmission (CoMP) are generally discussed. In this paper, we propose a cluster-based hybrid access strategy using non-cooperative game theory for the ultra-dense HetNet. In this strategy, we fully consider the possibility of CoMP transmission in the small cell cluster and introduce an enhanced signal to interference and noise ratio (SINR) measurement mechanism at the user side to further estimate the users' SINR under CoMP transmission mode. Then we take the load condition of the cells into account and formulate a non-cooperative game to assist the users to access to the best cell. The existence of Nash equilibrium is proven under feasible utility functions. Based on the different resource management mechanisms of small cells in the same cluster, we analyze our strategy under two kinds of cluster modes: distributed cluster mode and centralized cluster mode. The simulation results show that our strategy can achieve a considerable user throughput gain and better system performance compared to other strategies.