How does a Link 16 terminal passively obtain fine synchronization?

A Link 16 terminal achieves fine synchronization primarily by receiving three PPLI (Position, Phase, and Location Information) messages from three different sources. This method allows the terminal to triangulate its position and synchronize its internal clock with high precision. The requirement for multiple sources is crucial, as it helps to validate the timing and accuracy of the received data. Triangulating data from three distinct terminals ensures that the final calculated synchronization is robust and reduces the potential impact of any anomalies or errors from individual sources.

Using just one PPLI message may not provide sufficient information for accurate synchronization. Additionally, syncing with a primary user terminal or continuously broadcasting time signals does not inherently ensure the fine level of synchronization needed—both methods are part of the broader operation but do not serve the purpose of achieving fine synchronization in the way that receiving three PPLI messages does.