translate English to German: But in this case, the correction data are transmitted from a local source, typically at an airport or another location where accurate positioning is needed. These correction data are typically useful for only about a thirty to fifty kilometer (20-50 mi) radius around the transmitter.
Auf diese Weise ist eine Genauigkeit von ± 1 bis ± 10 mm pro km Abstand zur Basisstation zu erreichen.