MAC protocols for ultra-wideband ad hoc and sensor networking: A survey

Ultra-wideband (UWB) transmission is an emerging wireless communication technology that is gaining significant interest for future broadband wireless access. This transmission technique based mainly on the Impulse-Radio (IR) paradigm, has the potential to deliver high-speed wireless connectivity at low power and low proximity, characteristics that makes it an ideal choice for wireless sensor networks (WSNs). The distinct physical layer properties call, however, for innovative solutions at the medium access control (MAC) layer. Various MAC protocols with different objectives were proposed for these pulse-based networks. In this article, we first outline the issues related to MAC layer design relying on an IR-UWB physical layer. Then, we describe several MAC protocols emphasizing their strengths and weaknesses. Finally, we identify the cross-layer dependencies between the specified physical and the higher layers of the communication stack and investigate open research issues.