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Re: Why Don't We Have Land Based Positioning Systems?

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Am 25.07.2015 00:29, schrieb Henry Wilson DSc.:
> The advantages of a satellite based GPS is that it can be detected at almost
> any point on Earth, independent of terrain. However there are many
> applications where a local land based system would be perfectly suitable and
> much cheaper and more accurate.
> For instance, players on a football field are now being tracked with GPS
> during the game. That could be far better achieved with a triangle of
> transmitters set around the playing field. This would eliminate the inherent
> delays experienced when using GPS.
>
> By broadcasting time signals from a grid of towers, such as those already set
> up for mobile phones, a simple receiver could locate a person just about
> anywhere and with high accuracy.  Clock synching would be much easier and the
> distances between broadcast points is fixed and not continually changing as
> with the GPS.
> Why the heck hasn't someone set this kind of system up already when most of
> the towers are already in place. It would not even require the extreme
> accuracy of atomic clocks since they cold be .constantly synched with a master
> clock


It is not a question of usability, cheapness or accuracy, but a question 
of technological dominance the USA claims to posses.

Their entire defence system is based on their assumed advanced 
technology and what they exclusively control.

So, why should the US-military allow or build competing systems to GPS, 
that they exclusively control?


TH

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Re: Why Don't We Have Land Based Positioning Systems? Thomas Heger <ttt_heg@web.de> - 2015-07-26 09:16 +0200
  Re: Why Don't We Have Land Based Positioning Systems? Fabian Russell <root@localhost.localdomain> - 2015-07-26 07:45 +0000
  Re: Why Don't We Have Land Based Positioning Systems? Henry Wilson DSc. <hw@....> - 2015-07-29 07:45 +1000

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