Adaptive joint call admission control scheme in LTE-UMTS networks

Efficient radio resource management (RRM) is the need of next generation networks. Increasing demand of high-bit rate services together with limited availability of radio resources, needs a smart RRM strategy that can also maintain Quality of Service. Current penetration of Universal Mobile Telecommunication System (UMTS) as cellular technology is high. Also, Long Term Evolution (LTE) is an emerging technology, operators will face long periods in which both Radio Access Technologies (RATs) will coexist. A smart use of radio resources in both RATs will be of high interest for operators. In this paper, we discuss how efficient RRM can be exploited to facilitate more smart use of available radio resources for LTE and UMTS scenarios. Hence, we propose an adaptive Joint Call Admission Control (JCAC) model in LTE-UMTS networks which is capable of balancing loads among LTE and UMTS interface along with maintaining QoS requirements. The performance metrics such as load on two interfaces, system throughput, delay of interactive users are obtained using adaptive JCAC model. Further, the above metrics are compared with the results of Service-based and Load-based JCAC schemes on LTE-UMTS networks. The simulations are performed in QualNet 6.1 network simulator and the simulation results of proposed model are validated via analytical model using generalized stochastic Petri net.