NACA: A New Adaptive CSMA/CA Algorithm of IEEE 802.15.4 in Beacon-enabled Networks

In this paper, we propose a new adaptive CSMA/CA algorithm (NACA) that aims to reduce redundant transmission of IEEE 802.15.4 LR-WPAN. In wireless sensor networks (WSN), energy consumption is one of the most important issues. Furthermore, it makes the network life-time longer by reducing retransmission. To achieve this goal, we improve the carrier sensing features in MAC layer of IEEE 802.15.4. When the network is busy, the MAC detects it and adaptively chooses the parameters of CSMA/CA mechanism to minimize collisions and redundancy of retransmission packet based on the NACA. We evaluated the proposed scheme with original 802.15.4 MAC on the ns-2 simulator. The results show that our scheme outperforms the original by about 15% in case of retransmission.