Call Admission Control for Two-Tier LTE Macro/Pico Cellular Networks

The demands for traffic and services through the mobile networks are ever increasing. Multi-tier has become a major trend in the design of new generations of mobile networks such as advanced long term evolution (LTE-A) networks in order to support the high capacity demand required for multiservice traffic in wireless networks. Picocell emerged as one of the key radio access techniques for LTE-A networks to increase the LTE-Advanced coverage and capacity requirements in a cost-efficient way. Two-tier networks, comprising a LTE Macro-cellular network overlaid with shorter range and low power Picocells offer an economically important approach to improve the LTE-A network capacity. In this type of network an efficient call admission control scheme is required to improve the connection level Quality of Service (QoS) of the wireless networks in terms of dropping probability, blocking probability and resources utilization. This paper proposes a two-tier call admission control scheme for integrated LTE-A/Picocells to efficiently utilized the available resources and improve the network coverage. We compare and evaluate the proposed CAC in single and two-tier LTE-A networks. The results shows that using two-tier CAC with Picocell resource sharing increases the performance of the system in term of high utilization and blocking probability reductions.