Intelligent network synchronization for energy saving in low duty cycle MAC protocols

Several MAC protocols such as S-MAC, T-MAC, DSMAC, and TEEM have exploited scheduled sleep/listen cycles to conserve energy in sensor networks. These protocols use periodic SYNC packet in their SYNC period to follow the same schedule with their neighbors. We have found that these protocols use around 40% of their listen period for SYNC period. In an average, unused SYNC periods consume more than 20% of the total energy consumption. In this paper, we analyze the periodic nature of SYNC packet and develop a new algorithm, named as intelligent network synchronization (INS), which exploits the periodic nature of SYNC packet to reduce energy consumption. The proposed INS makes nodes bypass their own SYNC period by monitoring sleep/listen cycles of their each neighbor. We evaluate INS through both mathematical analysis and simulation. These results show the achievement of up to 25% of energy saving.