Submitted papers on WiMAX:

Delay Model for IEEE 802.16 Networks
Abstract - In this paper, we propose an analytical model to evaluate average packet delay and its standard deviation in a saturated IEEE 802.16 network. In addition, bandwidth utilization of an uplink data frame and the packet loss probability are also derived from the model. We show that our analytical model is accurate for a range of parameters by comparing it with simulation results. Using the analytical model we then suggest an appropriate parameter setting for the uplink data frame to better utilize the bandwidth and to minimize packet loss probability for both saturated and unsaturated networks.

(We have developed an event-driven simulation program using C++ to produce simulation results for this paper. To download the executable file of this simulator for SPARC/Solaris platforms, please click  here. )

Performance Evaluation of Contention-based Services in Unsaturated IEEE 802.16 Networks
Abstract - The IEEE 802.16 based WiMAX technology has great potential for the fourth-generation mobile networks. Some of its service classes use the contention based broadcast polling mechanism to request resources. In this paper, we investigate the performance experienced by these services when the network is unsaturated. In particular, we model each subscriber station as an M/G/1 queue where the service time is determined by the parameters of the network configuration and the binary exponential backoff contention resolution algorithm. We develop a fixed point analysis to derive analytical expressions for network throughput and packet access delay. The accuracy of the analytical model is validated by comparing with simulation over a wide range of operating conditions. The implications of various different parameter configurations on the performance are investigated using the analytical model. Moreover, we show that the model can be degenerated to the saturated condition. The utility of both the unsaturated and saturated models is further demonstrated by finding the optimal parameters which maximize the network throughput.

(We have developed an event-driven simulation program using C++ to produce simulation results for this paper. To download the executable file of this simulator for SPARC/Solaris platforms, please click  here. )