CA-MAC: A Hybrid context-aware MAC protocol for wireless body area networks

In wireless body area network (WBAN), various data sources are generated by different type of sensors and transmitted to the master node, which may result in temporally different traffic loads. With time-varying channel caused by frequent body movement, transmitted data may also experience deep fading and packet loss. To meet the complex transmission requirements in WBAN, a traffic-aware and channel-aware MAC protocol is required. In this paper, we introduce CA-MAC, a context-aware MAC protocol using a hybrid of contention-based and TDMA-based approaches. A dynamic control mechanism is proposed to address fading channel by adaptively modifying MAC frame structure. Schedule-based and polling-based techniques are also used to manage periodic, bursty, and emergency traffic requirement. Simulation results confirm the advantage of CA-MAC on reliability over existing TDMA-based approach.