Delay-aware call admission control algorithm in 3GPP LTE system

Long Term Evolution (LTE) has being standardized by the 3rd generation partnership project (3GPP) as the evolution of WCDMA. Different from the conventional mobile communication technologies that deliver voice traffic through circuit switched networks, in LTE, all kinds of traffic are transferred through packet switched networks based on Internet Protocol (IP). In order to provide Quality of Service (QoS) in packet switched networks, radio resource management (RRM) is very important. Especially, call admission control (CAC), which is a part of RRM, plays an important role in RRM because it can prevent network congestion and guarantee certain level of QoS for on-going calls by accepting or rejecting service requests. In this paper, we propose delay-aware CAC algorithm in order to provide QoS for various kinds of services in LTE system. Delay-aware CAC algorithm utilizes statistical datas for packet delay and PRB utilization in order to guarantee packet delay requirements for on-going calls. In order to evaluate performance of delay-aware CAC algorithm, we perform simulations under various environments. The simulation results show that the delay-aware CAC algorithm can satisfy packet delay requirements for various service types defined in LTE specification.