Author Topic: How are vessels appearing where there is no ground station nearby?  (Read 11256 times)

Marcus

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On the AIS map at marinetraffic.com, I often see vessels appear where there does not seem to be a ground station nearby, like off the coast of Antarctica.  When I click on the vessel's detail, it doesn't indicate which ground station the transponder's signal was received by.  How is this possible?  Are some vessels reporting by satellite, or some way other than VHF?

For example:

XUE LONG
Vessel's Details
Ship Type: Other
Year Built: 1993
Length x Breadth: 167 m X 25 m
DeadWeight: 8759 t
Speed recorded (Max / Average): 13.9 / 9.5 knots
Flag: China [CN]
Call Sign: BNSK
IMO: 8877899, MMSI: 412863000
Last Position Received
Area:
Latitude / Longitude: -68.68346˚ / 74.55846˚ (Map)
Currently in Port:
Last Known Port:
Info Received: 0d 0h 34min 18s ago
Current Vessel's Track
Itineraries History
Voyage Related Info (Last Received)
Draught: 8.5 m
Destination: ANTARCTICA
ETA: 2010-11-30 09:00
Info Received: 2010-11-23 08:27 (48d, 17h 41min 9s ago)
« Last Edit: 11 January, 2011, 05:01:21 am by Marcus »

Peter

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Re: How are vessels appearing where there is no ground station nearby?
« Reply #1 on: 14 January, 2011, 11:50:50 am »
There are several possible reasons:
1) wrong GPS data
2) wrong data received - this happens often when data is received with radioscanner/soundcard and error checking is turned off

Redtin

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Re: How are vessels appearing where there is no ground station nearby?
« Reply #2 on: 23 February, 2011, 01:13:16 am »
There are a few roaming stations around, eg a few of the supply vessels seen around here lately upload to the internet via satellite. There was data on marine traffic recently of vessels in the northern north sea , the station uploading apparently was in Australia. Suspect it was the greenpiece vessel which was in the area at the time hanging around a drilling ship.

Hoornend

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Re: How are vessels appearing where there is no ground station nearby?
« Reply #3 on: 12 December, 2013, 09:16:07 am »
Доброго времени суток!
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