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Emergent Slot Synchronization in Wireless Networks
May 2010 (vol. 9 no. 5)
pp. 719-732
Alexander Tyrrell, DOCOMO Euro-Labs, Munich and University of Klagenfurt, Klagenfurt
Gunther Auer, DOCOMO Euro-Labs, Munich
Christian Bettstetter, University of Klagenfurt and Lakeside Labs GmbH, Klagenfurt
This paper presents a biologically inspired approach for distributed slot synchronization in wireless networks. This is facilitated by modifying and extending a synchronization model based on the theory of pulse-coupled oscillators. The proposed Meshed Emergent Firefly Synchronization (MEMFIS) multiplexes synchronization words with data packets and adapts local clocks upon the reception of synchronization words from neighboring nodes. In this way, a dedicated synchronization phase is mitigated, as a network-wide slot structure emerges seamlessly over time as nodes exchange data packets. Simulation results demonstrate that synchronization is accomplished regardless of the arbitrary initial situation. There is no need for the selection of master nodes, as all nodes cooperate in a completely self-organized manner to achieve slot synchrony. Moreover, the algorithm is shown to scale with the number of nodes, works in meshed networks, and is robust against interference and collisions in dense networks.

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Index Terms:
Wireless communications, meshed networks, distributed systems, emergence, self-organization, medium access control (MAC), slot synchronization, firefly synchronization.
Alexander Tyrrell, Gunther Auer, Christian Bettstetter, "Emergent Slot Synchronization in Wireless Networks," IEEE Transactions on Mobile Computing, vol. 9, no. 5, pp. 719-732, May 2010, doi:10.1109/TMC.2009.173
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