Wireless Picosecond Time Synchronization for Distributed Antenna Arrays with Dynamic Connectivity

TL;DR

This paper introduces a decentralized, high-precision time synchronization method for distributed antenna arrays with dynamic connectivity, achieving picosecond accuracy and robustness to network changes and node failures.

Contribution

It presents a novel decentralized synchronization approach combining average consensus and two-way time transfer, effective under changing network topologies and failures.

Findings

Achieved synchronization precision under 3 ps in fully connected networks.

Demonstrated robustness to node failures and network adversities.

Validated method through simulation and experimental implementation.

Abstract

Phase, time, and frequency coordination are crucial for the coherent operation of distributed antenna arrays. This paper demonstrates a high accuracy decentralized time synchronization method for arrays with dynamic connectivity. To overcome challenges such as alteration in network topology, system scaling, and single- or multiple-node failures, we present a decentralized time synchronization method implementing the average consensus algorithm and two-way time transfer. Our approach supports decentralized time synchronization with picosecond accuracy ($< 13$ ps), unbiased convergence, resilience to node failures, and robustness to other network connection adversities. A time synchronization precision of under 3 ps was achieved for a fully connected frequency syntonized network. The algorithm ensured convergence in time even for a network with only one link connecting two randomly chosen nodes at each iteration; however, the speed of convergence decreased along with the number of connected links. The method is exhibited for a six-node distributed array, by both simulation and experimental implementation using software defined radios.