Time and frequency synchronization in multistatic radar. Consequences to usage of GPS disciplined references with and without GPS signals

The use of time and frequency references disciplined to GPS has been studied in the context of use in multistatic radar. Several reference units with civilian GPS receivers were tested. Differences in 1PPS fluctuations were observed that would result in ranging errors when stable GPS signals were received. If GPS signals were lost further control of reference output depends on the stability of the reference unit. Drift in frequency and corresponding time deviation were observed according to reference quality. The stable rubidium references were found to give reliable synchronization output for a long time without synchronization.