[Int-area] GPS over wifi

[Rob Brew <[e-mail]>]

Hi,

Except when you can install a GPS repeater.

We already have wireless networks covering each area of tube stations, this
makes the porvisioing of such functionality cheaper as the
infrastructure is already there,


I need to look at it.

Until then, I can tell that there is a GPS GATE software that captures
GPS signals and puts the data (NMEA?) on IP and distributes it to IP
receivers.  These IP receivers might be on WiFi too.

In this case, it might be that one needs to tell what is the format of
NMEA over IP.  It's very simple.

But, agreeing that NMEA is the best thing is a different thing.  On one
hand, NMEA has new versions.  But it uses WGS84 which might not be the
best coordinate system - it is good for smartphones and users, maybe
cars, but in some countries it is not used to locate some important
points.  These use other coordinate systems.  So maybe one wants to come
up with a more universal coordinate system that makes everyone happy,
and take _that_ and put on WiFi (not NMEA).  Because, IP is such
universal, we should put universal things on it.

Conversions between systems are huge opportunities for glitches to get
in.  These kinds of glitches ahppening very fast and added up may lead,
and have led, to disasters.

> As we know the IP Address contacting the server the server contains a
>  map containing the GPS location of each underground site, as
> referenced by IP address.  The  returns the phsycial GPS location and
> name of the site as a JSON array.
>
> To prevent false servers reporting inaccurate information https can
> be used to verify the authenticity of the server.
>
> Providing this service to mobile phone user's without a current WIfi
>  connection i propose going one stage further, create a hidden
> wireless network wih the name ".location". In cases where no GPS
> location can be found a mobile phone's GPS system can be programmed
> to seek such a network providing the same service.

Hold on, 'hidden wireless network', make sure 'hidden terminal problem'
is distinguished.

A phone that cant have WiFi connection - what kind of other IP
connection does it have, in a place that has no GPS coverage?  Is it a
cellular connection in underground metro station?  If yes, it means
either there are cellular base stations there, or there are cellular
repeaters: enhance them to repeat GPS as well.


> This would require alterations to th servics as provided by mobile
> phone providers such as Apple and Android.
>
> If you are interested in this concept please review it (and my code),
>  and maybe it will become something. For a video demonstration of
> this service please check the link at the github site.

I will look at the draft later.

Alex