Distributed Synchronization For Ad-Hoc Acoustic Sensor Networks Using Closed-Loop Double-Cross-Correlation Processing

With the demand of signal processing in wireless acoustic sensor networks (WASNs), network-wide synchronization is required to exhaust their potential in signal enhancement. This paper delivers a gossiping approach for distributed synchronization using waveform-based estimation of sampling rate offset (SRO) by the double-cross-correlation processor (DXCP). Each node receives a local reference signal one-way, either from the reference node or from a parent on rooted-tree topologies. The proposed method then operates closed-loop with DXCP-based SRO estimation and resampling to the local reference. We demonstrate how the synchronization gossip propagates network-wide for various configurations of the topology. Synchronization performance is assessed by evaluation of settling time, estimated SRO values and output signal-to-synchronization-noise ratio of resampled waveforms on simulated WASN data.