Decentralized Inter-Base Station Synchronization Inspired from Nature

The present article develops a decentralized inter-base station slot synchronization algorithm suitable for cellular mobile communication systems. The proposed algorithm is derived from the theory of pulse-coupled oscillators, commonly used to describe synchronization phenomena in biological systems, e.g. spontaneous synchronization of fireflies. In order to maintain synchronized base stations (BSs), even when there is no direct link between them, some selected user terminals (UTs) participate in the network synchronization process. Synchronization emerges thanks to two synchronization words, one transmitted by BSs and the other by UTs, and each group helping the other synchronize. It is demonstrated through simulations that in a typical indoor environment, synchronization is always achieved within 10 super-frames when coupling parameters are appropriately chosen, without any a priori assumption on the initial timing misalignments of BSs and UTs.