Low complexity adaptive schemes for energy detection threshold in the IEEE 802.15.6 CSMA/CA

IEEE 802.15.6 is a radio interface standard for wireless connectivity of wearable and implantable sensors located inside or in close proximity to the human body (i.e. a Body Area Network). Medical applications requirements impose stringent constraints on the reliability, and quality of service (QoS) in these networks. Radio interference from other co-located BANs or nearby devices that share the same spectrum could greatly impact the data link reliability in these networks. The CSMA/CA MAC protocol as outlined in the IEEE 802.15.6 BAN standard involves the use of an Energy Detection (ED) threshold to determine the status of the transmission channel i.e. idle versus busy. In our previous work, we have shown that the use of such static thresholds negatively impacts the performance of the system composed of multiple co-located BANs, leading to possible starvation or unfair treatment for several nodes. This paper proposes low complexity schemes that can be used to adapt the ED threshold in transmitting nodes of a BAN. The objective is to fairly allow channel access to all nodes regardless of the level of interference that they are experiencing. Simulation results indicate benefits of the proposed strategy and demonstrate improvement in the overall performance.