GPS is not a 'colloquialism' it is a term with a precise meaning.
Correct. Global Positioning System refers to a specific system involving specific kinds of spacecraft in specific orbits, used with specific kinds of receivers on or above Earth's surface. It refers to a specific mathematical basis for three-dimensional triangulation.
Earlier satellite networks provided a different kind of geolocation, using different satellites in low Earth orbit and a completely different mathematical model. For SAR purposes, the transmitter is at the site of interest (e.g., a sunken ship, an aircraft crash, or a lost hiker). The transmitter broadcasts continuously on a steady frequency. The curve of Doppler distortion as received by the satellite can be fit mathematically to parameters that describe how far to the left or right of the satellite's ground track the transmitter is. (This is why the transmitters must be very carefully calibrated to transmit in a narrow band.). The curve of amplitude variation over time, as received by the satellite, determines the point along the satellite's ground track that is closest to the receiver, but this too can often be gleaned from the Doppler curve. Either way, all this requires someone on the ground to interrogate the satellite for that information and carry out some suitable exercise.
Early navigation used the same math in reverse. The satellites emitted a steady radio signal on a particular frequency. Ground stations equipped with a suitable receiver could fit the Doppler and amplitude curves as they received them to obtain their position relative to the satellite's (known) ground track. The receivers we used in the 1980s were about the size of a breadbox and required setting up an ungainly antenna. Not something you can stuff into a small buoy, and -- operating in this mode -- not very helpful for the required purpose.
GPS works entirely differently. By using atomic clocks and stable, high-speed timers, the receiver works out the distance from several satellites themselves, not from the satellites' ground tracks. The signals are pulses containing digital information, not steady signals. The satellites are in much higher orbits, and don't care (or even know) who might be receiving their signals. The system provides no method for a ground station to signal its whereabouts such that a third party knows where it is.
That some journalist may not know the difference between various satellite systems is par for the course, it appears, for some journalists. GPS is not a generic term for any satellite-based system.
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