A Self-Adaptive Superframe Structure for Emergency Traffic Based IEEE 802.15.6

IEEE 802.15.6 is primarily designed for the Wireless Body Area Networks (WBANs), which provides a base for the wearable and implantable sensors. These sensors are tiny nodes used to collect information and sent to a central controller called hub. In a star topology, the hub is responsible to transmit a key superframe bounded by the beacon. The superframe is an important attribute of the beacon-enabled mode of IEEE 802.15.6. The superframe structure is divided into exclusive access, random access, and managed access phases along with a contention access phase. However, currently, the superframe structure of IEEE 802.15.6 is static in nature and cannot adapt itself for emergency and regular traffic. Emergency traffic is the most important data which needs to be transmitted reliably and correctly in order to timely monitor the patient. Due to the fixed superframe structure, emergency traffic causes packet loss and delay. In order to alleviate packet loss and delay, we present a self-adaptive superframe (SAS) algorithm. The SAS algorithm adjusts the EAP phase for emergency traffic based on the network traffic, packet delivery, packet loss ratio, and the observed network delay to enhance the network performance. The results show that the SAS algorithm adapts itself based on the network conditions and adjusts the EAP phase efficiently and outperforms IEEE 802.15.6 in terms of delay, packet delivery ratio, and throughput.