An Analytical Model for Prioritized Contention Access in ECMA-368 MAC Protocol

The European Computer Manufacturers Association (ECMA) International recently defined the ECMA-368 standard, which specifies the physical and media access control (MAC) layers for Ultra Wideband (UWB) based wireless personal area networks (WPANs). The MAC protocol in ECMA-368 has a superframe structure. Each superframe is divided into three different time periods. One of them is the prioritized contention access (PCA) period which supports contention-based access between different traffic classes. In this paper, we propose an analytical model to evaluate the performance of PCA in ECMA- 368 MAC protocol. We assume that packets follow the Markovian Arrival Process (MAP) and various service times can be modeled by different phase type distributions (PHs). We apply the Matrix Geometric Method (MGM) technique and model the system as a MAP/PH/1 queueing system. We derive the probability mass function for the number of the packets in the queue, and the cumulative distribution function for the packets´ waiting time. The correctness of our proposed analytical model is validated via OPNET simulations.