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Playing the devil’s advocate here. If sats are a hoax, why does a TomTom work on an airplane?
Surely, it can’t be ground-based stations as we all agree the 9/11 cell phone calls on those planes were a hoax.
My best guess is it’s a ground based system using a connected bank of antenna farms (HAARP?). They bounce off some ceiling, whatever height that may be. This could explain why a receiver works.
Satnav / GPS / Tomtom uses exactly the same transmission technology as broadcast “satellite” TV – ionospheric refraction.
There are no “satellites”, and never have been.
GPS is a one-to-many broadcast system, as opposed to a point-to-point transmission.
The GPS transmitters are all ground-based, and have antennae that generally take the form of large parabolics – giant “satellite” dishes with motorised elevation controls.
These ground-based antennae direct a GPS signal at the ionosphere (an electrically-charged layer of the atmosphere). The GPS signal is directed at the ionosphere from a very acute angle compared to the earth normal (plumb vertical being 90deg).
When the GPS signal hits the ionosphere it refracts (bends) back down towards the earth’s surface where it can be received. The beam angle of the transmitter is wide, causing wide signal dispersion, ensuring maximum coverage of the GPS signal by our satnavs/TomToms, with their non-directional antennae.
This refractive process is defined in a formula known as the Appleton-Hartree Equation. In Appleton’s day (1920s-), the formula was very simple, but as more variable were discovered, the Equation has become ever more complex.
Key variables include the radio frequency of the signal, latitude, earth temperature, hour of day, time of year, sun-spot cycle, and so on.
All of these variables individually affect the refractive altitude of the ionosphere.
The refractive altitude of the ionosphere starts at just a few tens of kilometres, perhaps averaging at 100-150km (for a microwave frequency signal), with a maximum refractive altitude of about 600km.
The GPS system works by calculating time differentials. These are the differences between the time-of-arrivals for several GPS signals, each sent from a separate fixed ground point.
Each of those GPS signals is low bit-rate, to reduce transmission errors introduced by that signal dispersion. And each GPS signal contains a precision timestamp added by the transmitter. All of the GPS transmitters have synchronised local clocks.
There is a real-time feedback system (HAARP et al) which relays ionospheric altitude measurements (calculated from ionosonde probing) to the transmitter sites.
And the timestamp included by a transmitter in its GPS signals is individually adjusted, according to the current refractive altitude of the ionosphere, measured at the point of refraction for that transmitter.
Knowing:
(i) the fixed geo-location of a GPS transmitter;
(ii) the current refractive altitude of its signal
(iii) the transmission timestamp in a GPS message
(iv) the time of arrival of a GPS message
(v) the speed of lightThese (i)- (v) are used to calculate the distance from a transmitter to the receiver.
By combining at least three of these distances, it’s possible through triangulation to determine the geo-location of the receiver itself.
These days, GPS geo-location has an accuracy of a few tens of millimetres. Precision is only limited by the accuracy of the local clocks, and the accuracy of the ionosonde probing.
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