Evaluation of guard channel admission control schemes for IEEE 802.16 with integrated nb-LDPC codes

WiMAX (Worldwide Interoperability for Microwave Access) based upon the IEEE 802.16 standards is a promising technology for the “last mile” wireless Internet access. In order to provide required QoS level to different service flows and to prevent base station (BS) from running out of resources dedicated connection admission control (CAC) algorithm has to be implemented. Since the introduction of IEEE 802.16e specification, a lot of studies have focused on development of CAC. In this paper authors present the ns-2 module with integrated Connection Admission Control support. Two admission control algorithms are discussed, modified and eventually the DHCAC is implemented. Evaluation of the ns-2 system level simulation environment integrated with the IEEE 802.16 physical layer implemented as Simulink model is presented. It is shown that it is possible to successfully integrate ns-2 with external model of physical layer (Simulink). Moreover simulation results for modified DHCAC are compared to results obtained using the integrated platform with DaVinci nb-LDPC codes implemented.