A Medium Access Control of Prioritized Contention Access in Ultra Wide Band Home Networks

Wireless personal area networks (WPANs) are becoming a popular way of networking computer equipments in the home and office. In order to support differentiated quality-of-service (QoS) in WPANs, the ECMA-368 prioritized contention access (PCA) protocol allocates multiple access categories (ACs) with different priorities, inter-frame spaces, and contention window sizes. This paper presents an improved medium access control (MAC) scheme to enhance the QoS of WPANs based on the idea of using the different increasing functions for each AC to enlarge the size of contention window in the case of transmission collision. The performance of this improved scheme under multimedia applications is extensively investigated and compared with the original ECMA-368 PCA using the well-known network simulator NS-2. The results show that this scheme is able to achieve higher throughput and medium utilization than the original ECMA-368 PCA. Moreover, it provides a good prioritization level between multiple ACs.