Sissy
11/03/2008
05:38:28 PM
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Re: Differential Corrections
In the old days of the beginnings of GPS, reference stations (stationary receiving stations) were usually provided by big companies, like offshore oil drilling firms or surveying companies. In those days and up to this time, you buy or establish a reference receiver and link up your roving receivers to it.
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Jacob
11/03/2008
05:39:12 PM
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Re: Differential Corrections
Nowadays, there are public agencies that are transmitting GPS corrections for the public, sometimes for free. Once of these is the US Coast Guard; some are international agencies. Most of these free GPS reference stations are near major waterways and landing harbors.
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Basil
11/03/2008
05:40:08 PM
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Re: Differential Corrections
Moreover, most of these stations transmit radio waves to beacons that are already existing and capable of receiving these radio waves which are usually in the 300khz range.
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