Reliability Evaluation and Enhancement of IEEE 802.15.4 Slotted Contention Scheme

IEEE 802.15.4 is a current major technology for low- rate low-power wireless personal area networks (WPANs). To study the reliability of its medium access control (MAC) function, in this paper we evaluate its packet dropping rate performance with focus on the reason to drop a packet. Considering the compatibility with the original protocol, when the access failure happens the packet isn´t dropped directly but kept to be retransmitted. Comparing with the original protocol through the simulations, the revised scheme decreases the dropping rate apparently. In addition, the revised scheme saves more energy not only for an end device but also for the PAN coordinator.