Adaptive cooperative communication for maximizing reliability and reward in ultra-dense small cells LTE-A toward 5G cellular networking

The Long Term Evolution-Advanced (LTE-A) release 12 specification proposes the small cell enhancement technology that can increase system capacity in the indoor/outdoor hotspots, increase wireless coverage, improve signal quality, reduce the eNB deployment cost, etc. By deploying several small cells in the original LTE-A network, it forms a Heterogeneous Network (HetNets) for achieving cooperative communications. Although the small cell-based HetNets brings above-mentioned advantages, HetNets suffers from increasing interference yielded by neighbor small cells, yielding more inter-cell and intra-cell handoffs, etc. Definitely, several critical issues should be addressed effectively, including 1) the inter-cell interference among several neighbor small cells, 2) the issue of cell selection with a various-scale cells cooperation, 3) the multi-cell cooperative communication for minmizing carrying and maximizing bringing reward, and 4) improving LTE-A radio Resource Block (RB) utilization. This paper thus proposes the Adaptive Cooperative communication for Ultra-Dense LTE-A toward 5G HetNets (namely ACU). The contributions of ACU include: 1) the link reliability determination of the cooperative candidate cells (LRP), 2) Adaptive maximum throughput and QoS-based real-time priority for UEs (AMP), and 3) the Cost-Reward-based optimal Cooperative Communication (CRCC). Numerical results show that ACU outperforms the compared approaches in system capacity, RB loading, net-profit, reward, average packet dropping probability and average packet delay.