Accurate positioning by Low Frequencies (ALF)

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Accurate positioning by Low Frequencies (ALF)
ALF-RDS.jpg
Frequencies 123.7 kHz
Frequency Range 123.7 kHz - 123.7 kHz
Mode USB
Modulation PSK
ACF
Emission Designator
Bandwidth 2.1 kHz
Location Germany
Short Description Accurate positioning by Low Frequencies, a former German DGPS navigation system. No longer in use as of 2013.
I/Q Raw Recording
Audio Sample

Accurate positioning by Low Frequencies, a former German DGPS navigation system. No longer in use as of 2013

The system serviced all of Germany, with a 600 km - 800 km range from the transmitting antenna near Frankfurt.

This signal operated at 1187.6 BaudBaud (unit symbol Bd) is the unit for symbol rate or modulation rate in symbols per second. and used BPSKBinary Phase-Shift Keying (1 bit per symbol) modulation. This signal also used the RDS format used in commercial FMFrequency Modulation sidebands for the low bitrate dissemination of information. This version of RDS was transmitted in SSBSingle-sideband modulation with a decreased pilot level to reduce the bandwidth.

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Professional Equipment/Software

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