Journal of Communications
In many synchronized MAC protocols for wireless sensor networks such as IEEE 802.15.4 in beacon enabled mode, periods where all the nodes are active alternate with periods where all the nodes are inactive. This approach is used in order to save the energy of nodes as they are powered by small batteries. However, having all nodes active simultaneously can yield to congestion, which increases the packet loss rate and the delay. In this paper, the authors propose a new MAC scheduling mechanism that distributes the activities of nodes into several periods, thus reducing the number of active nodes during each period.