MLAT relies the time difference of arrival from various modes messages based on the speed of light. To compute this time difference requires extremely precise timing between the various base stations.

Traditionally, MLAT calculations have used the timing signal from GPS satellites to precisely determine the time of arrival. However, the new Fr24 pi software does not need GPS to participate in MLAT calculations. I understand that users need to input their own coordinates - no issue there - but how is the timing so precisely computed? There must be a timing signal coming from somewhere?

Traditionally, MLAT calculations have used the timing signal from GPS satellites to precisely determine the time of arrival. However, the new Fr24 pi software does not need GPS to participate in MLAT calculations. I understand that users need to input their own coordinates - no issue there - but how is the timing so precisely computed? There must be a timing signal coming from somewhere?

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