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Sunnyvale, CA | Some RTK correction formats are open.
although Trimble created CMR (compact measurement records) for RTK corrections, the format was "donated" to the world wide community when Trimble published the CMR specification in the early '90s. RTCM ver 2.0 and 3.0 are other open standards with RTK messages. the RTCM from Coast Guard Beacon towers does not have the RTK messages of RTCM 2.0 or 3.0. The Beacons use MSK (minimum shift keying) modulation and transmit in the MF (medium frequency band) approximately 285 to 325 kHz. There is some experimental work to see if RTCM 3.0 RTK messages can be transmitted from Beacon or other low frequency sources. the difficulty seen is the bandwidth required for the RTCM correction stream for RTK. | |
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