Performance analysis of a new scheduler with call admission control (CAC) for IEEE 802.16 with delay bound guarantee

Abstract

WiMAX is a project developed by the Working Group of IEEE 802.16 standard for broadband wireless access networks in Metropolitan Area Network (MAN). One of the features of MAC layer, this standard, is that it is designed to differentiate service among traffic categories with different multimedia requirements. Based on these assumptions and considering that the standard does not specify a scheduling algorithm, a new scheduler with call admission control was proposed based on Latency-Rate (LR) server theory and system characteristics specified by the standard for systems using the WirelessMAN-OFDM (Orthogonal Frequency Division Multiplexing) air interface. The proposed scheduling algorithm calculates the time frame (TF) in order to maximize the number of stations allocated in the system while managing the delay required for each user. Properties of this proposal have been investigated theoretically and through simulations. A set of simulations is presented with both Constant Bit Rate (CBR) and Variable Bit Rate (VBR) and performance comparisons among with different delays and different TFs. The results show that the delay upper bound can be achieved for a large range of networks load with bandwidth optimization.