Towards Low-Delay Body Area Networks: An Investigation on the Hybrid MAC of SmartBAN and IEEE 802.15.6 Wireless Body Area Network

In anticipation of future ubiquitously-connected healthcare services with stringent delay requirements, we outline the main characteristics, design challenges and existing open issues in the medium access control (MAC) layer design of wireless body area networks (WBANs) and highlight the need to define hybrid MAC frame that enables flexible access according to traffic and services. For the first time, a thorough investigation of two WBAN standards, namely the IEEE 802.15.6 WBAN and the recently-proposed ETSI SmartBAN, in terms of delay and energy, is presented. We provide insights into the impact of MAC frame timing structure on delay and energy performances of these existing protocols. We compare the selections of access durations for the SmartBAN hybrid MAC frame and IEEE 802.15.6 superframe. Then, we present our simulation comparisons of the uplink delay and energy consumption in a SmartBAN and a IEEE 802.15.16 WBAN for healthcare, taking into account periodic monitoring and health-critical emergency traffic patterns. Our results emphasize that compared to IEEE 802.15.6-defined WBANs, SmartBANs are advantageous in energy-saving. Moreover, with a time-optimized MAC, SmartBANs reduce the delay for both periodic monitoring and emergency report.