Joint call admission control and load-balancing in ultra-dense cellular networks: a proactive approach

Cellular networks adopt call admission control (CAC) algorithms to prevent network congestion and guarantee quality of service (QoS) for user equipments (UEs). Conventional CAC algorithms accept or reject incoming calls based on radio resource availability. Those rejected calls may lead to network performance degradation. Collaboration of CAC and load-balancing can overcome such a problem. However, conventional joint schemes are reactive and proven time consuming; hence, inefficient in real-world scenarios. To overcome such problems as well as to improve network performance, we propose a proactive approach for joint call admission control and load balancing. The algorithm mitigates the number of rejected calls by performing proactive offloading. To that end, the algorithm identifies potential incoming UEs in a cell prior to handover. If a cell is fully occupied and an incoming UE is detected, the proposed algorithm hands over some of the edge UEs from that particular cell to its neighboring cells. As a result, the cell has enough resources to accept the incoming call. Simulation results show that the proposed algorithm reduces the number of unsatisfied UEs and maximizes network throughput by 11.04%, compared to a network without a CAC algorithm.