Performance Modelling and Analysis of the TXOP Scheme in Wireless Multimedia Networks with Heterogeneous Stations

摘要

The explosive growth in advanced multimedia applications poses great challenges for design and deployment of wireless communication networks. Transmission Opportunity (TXOP) is a promising MAC protocol extension for provisioning of differentiated Quality-of-Service (QoS) in multimedia WLANs. However, for analytical tractability and simplicity, most existing performance models of TXOP have been restricted to unrealistic working scenarios where the traffic is saturated or follows a Poisson process, which is unable to capture the heterogeneous characteristics of multimedia traffic. To fill this gap, this paper proposes an original analytical model for TXOP in WLANs with heterogeneous stations in the presence of multimedia applications. Specifically, the traffic generated by heterogeneous stations with background, voice and video applications is modelled by the non-bursty Poisson, bursty Markov-Modulated Poisson Process, and fractal self-similar process, respectively. QoS measures including throughput, end-to-end delay, and frame loss probability are derived. The extensive comparison between the analytical results and those obtained from simulation experiments subject to the traffic parameters of real-world voice and video sources validates the accuracy of the developed model for WLANs with practical multimedia applications. The performance results reveal the importance of taking into account the heterogeneous stations for the accurate evaluation of TXOP in wireless multimedia networks.