Fast Open-Loop Synchronization for Cooperative Distributed Beamforming

This paper considers the problem of multiple distributed nodes in a wireless network wishing to join forces and cooperatively beamform data to a destination. Since the nodes are not physically connected and have independent oscillators, there are carrier frequency and phase errors that degrade the beamforming performance. This paper proposes a novel open-loop synchronization protocol, which exploits the broadcast nature of the wireless channel to achieve synchronization much faster than prior methods, with the difference increasing as the number of nodes increases.