[FOSS-GPS] GPS in space?

[Fabrizio Giudici]

Risto H. Kurppa wrote:
> Hi!
>
> Does anyone know how well GPS works in the space? How high is it still
> reliable, what causes the possible errors and so on? If you take a GPS
> device beyond the geostationary level (where the satellites are?),
> what happens? I suppose some customization is required but a normal
> handheld GPS wouldn't handle it properly.
>   
If I'm not wrong the equations have two solutions, one for r < r0 and 
another for r > r0 (r0 is the geo-stationary radius). So, you'd need to 
give an input to the system about whether you're below or above r0, in 
order to choose the proper solution. Also, I've forgotten a lot about 
maths since the university, but I'd bet that in such cases, when r 
approaches r0 you've a lot of approximation, since the two solutions get 
closer.

-- 
Fabrizio Giudici, Ph.D. - Java Architect, Project Manager
Tidalwave s.a.s. - "We make Java work. Everywhere."
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