A clock synchronization scheme is crucial for obtaining accuracy in time-based positioning systems. Existing clock synchronization schemes are mostly based on a simplified linear clock model, which unfortunately have a poor long-term synchronization accuracy. Assuming a two-way time transfer protocol, we propose a novel clock synchronization algorithm based on a precise physical clock model to realize joint clock synchronization and propagation delay estimation. The Cramer-Rao lower bound (CRLB) is derived for this clock model and shows that the estimation is asymptotically efficient and converges to the lower bound. For long time spans, this model performs better than a linear clock model.
['Yan Xie', 'Gerard J. M. Janssen', 'Alle-Jan van der Veen']
A practical clock synchronization algorithm for UWB positioning systems