A method includes, at a first node: transmitting a first synchronization signal at a first time according to a first clock of the first node; back-coupling the first synchronization signal to generate a first self-receive signal; calculating a time-of-arrival of the first self-receive signal according to the first clock; and calculating a time-of-arrival of the second synchronization signal according to the first clock. The method also includes, at the second node: transmitting the second synchronization signal at a second time according to a second clock of the second node; back-coupling the second synchronization signal to generate a second self-receive signal; calculating a time-of-arrival of the second self-receive signal according to the second clock; and calculating a time-of-arrival of the first synchronization signal according to the second clock. The method S100 further includes calculating a time bias and a propagation delay between the pair of nodes based on the time-of-arrivals.