Channelized Frequency Synchronization Using Consensus Averaging for Distributed Phased Arrays

We demonstrate a novel channelized consensus frequency synchronization approach that enables separate radio-frequency wireless systems to converge at a consistent operating frequency, enabling distributed phase-coherent wireless operations. The approach is based on decentralized averaging, which is a consensus-based coordination approach. Nodes transfer their frequencies to neighboring nodes and calculate the average of their frequencies and their neighbors’ frequencies. The approach is decentralized, thus there is no single point of failure as in typical centralized approaches, and the consensus frequency is tolerant to adding nodes, dropping nodes, and drifting oscillator frequencies. We use a channelized approach where nodes transfer their frequencies on designated subcarriers, supporting full-duplex operation. We analyze the algorithm convergence through a proof-of-concept microwave wireless testbed using software-defined radios, demonstrating consensus frequency operation between four separate radios.