To exploit distributed computation in wireless sensor networks (WSNs) time synchronisation protocols are required. These protocols support advanced distributed and synchronous tasks between several nodes. Temperature changes have a strong influence in oscillators and may vary the clock of the nodes. The flooding time synchronisation protocol (FTSP) is a common time-sync protocol in WSNs. It cannot deal with rapid temperature changes and needs several long periods to readjust the clock drift. Proposed is an innovative correction factor, implemented in a module called advanced adjustment temperature (A2T), that minimises the impact of temperature in the clock skew. This module may be placed on top of any clock-skew based time synchronisation protocol with minimum coding modifications. For this work, the module has been linked to the FTSP, producing A2T-FTSP. Experiments show that A2T-FTSP reduces noticeably the average synchronisation errors compared to FTSP for the same varying temperature conditions.
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