A novel low-power time synchronization algorithm based on a fractional approach for wireless body area networks

Time synchronization is a topic of interest for any distributed system and it is of particular relevance in Wireless Sensor Networks (WSN), especially when it is necessary to keep a strong level of time synchronization among the data coming from different nodes, which are then employed to perform a posteriori data-fusion and data-merging operations. A special case of WSN is constituted by Wireless Body Area Networks (WBAN). The paper introduces the Fractional Low-power time Synchronization Algorithm (FLSA), a lightweight and ultra-low-power time synchronization algorithm conceived for Wireless Body Area Networks. The core of the proposed approach is the fractional-time concept, borrowed from Phase-Locked Loops theory, that allows achieving fine timer corrections. Moreover, an heuristic routine managing the on/off switching of the radio section of the device allows to dramatically decrease the power consumption. The mathematical discussion, along with a set of experiments is presented, proving the benefits associated with the proposed algorithm.