Backoff Algorithm Optimization and Analysis for IEEE 802.15.4 Wireless Sensor Networks

In wireless personal area network, a channel is shared by a number of nodes. Therefore packet collision may take place which degrades the system performance. To enhance the performance of slotted carrier sense multiple access (CSMA/CA) for IEEE 802.15.4 wireless sensor networks, we propose a collision-aware backoff algorithm (CABEB), which can dynamically select a suitable backoff period based on the collision probability of current network. In addition, a theoretical analysis based on Markov chain is proposed to derive a mathematical model for our proposal. The results of OMnet++ simulation indicate that the proposed backoff algorithm (CABEB) performs better than the previous IEEE 802.15.4 standard and KEB (knowledge-based exponential backoff).