OTSP: an optimised time synchronisation protocol for wireless sensor networks

In this work, we propose a new time synchronisation protocol for wireless sensor networks WSNs, called OTSP for "Optimised Time Synchronisation Protocol". The proposed OTSP works in three phases: neighbour discovery phase NDP, centre node-localisation phase, and synchronisation phase. The purpose of neighbour discovery phase is to provide neighbours' tables to the base station BS. Using neighbours' tables, the centre node is the localised and a hierarchical tree is created. After that, the centre node will synchronise its direct neighbours and will select among them a subset of coordinators nodes. Coordinators will then propagate the synchronisation message and will also select another set of coordinators to continue the synchronisation process. This process continues until the leaf nodes are synchronised. Simulations show the superiority of OTSP, and that it outperforms TPSN, and RTSP in terms of synchronisation tree depth, energy efficiency and synchronisation error, and TSST only in term of synchronisation error.