Differential omega

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A differential omega was the name given to a process in which correction signals were broadcast using small transmitters operated in the frequency range between long and medium waves in order to reduce errors in navigation using the Omega radio navigation system . Differential omega transmitters were mainly placed near port entrances. With the shutdown of the Omega navigation system on September 30, 1997, the differential Omega transmitters also became obsolete. A similar method is differential GPS (DGPS).