Performance Evaluation of Bandwidth Request in WiMAX Networks

Abstract

WiMAX have emerged as a promising wireless broadband access technology with throughputs comparable to wired DSL connections (digital subscriber line). Cellular deployment of WiMAX allows multiple subscriber connections with each base station. Bandwidth allocation to subscribers follows Demand Assignment Multiple Access (DAMA) where a subscriber is allocated the bandwidth based on its request. Performance of WiMAX deployment significantly depends upon the efficient bandwidth request and allocation. In this thesis, we investigate the bandwidth request and grant mechanism of WiMAX using Markov chain based analytical model. We study the impact of different parameters on the grant probability of bandwidth requests. Our analysis shows that grant probability is heavily dependent upon the probability of bandwidth request transmission without collision. We conclude that the grant probability can be improved significantly by reducing the wait time of subscribers after transmitting the bandwidth request.