Performance of a burst-frame-based CSMA/CA protocol for high data rate ultra-wideband networks: analysis and enhancement

Ultra-wideband (UWB) is a promising technology that can support high data rate communication for future Wireless Personal Area Networks (WPANs). To provide high throughput in UWB networks, we proposed a general framework for CSMA/CA based MAC protocol previously [17]. In this framework, multiple upper layer packets can be assembled into a single burst frame at the MAC layer, which can significantly improve the throughput performance by reducing overheads. Nevertheless, the burst assembly procedure may introduce extra packet delay, which is undesirable for some applications. In this paper, we address the performance issue in the burst-frame-based MAC protocol. In particular, we develop an analytical model to evaluate the delay performance of the burst-frame-based MAC protocol under unsaturated conditions. Our delay analysis is unique in that we consider the end-to-end packet delay, which is the duration from the epoch that a packet enters the queue at the MAC layer of the transmitter side to the epoch that the packet is successfully received at the receiver side. The analytical results give excellent agreement with the simulation results, which represents the accuracy of our analytical model. The results also provide important guideline on how to set the parameters of the burst assembly policy. Based on these results, we develop an efficient adaptive burst assembly policy so as to optimize the throughput and delay performance of the burst-frame-based CSMA/CA protocol.