No matter where you go, there they are.

[Paul_Koning/US/3Com%3COM at smtp1.isd.3com.com]

>Re spoofing the system.  If you think about the geometry of the
>problem, the delay to be induced for each satellite is a time
>varying function of the satellite's position, the reference site,
>and the target. It will vary from positive to negative values for
>many satellite passes.  It can be precomputed, but the precomputed
>adjustment will be in error by some amount due to the orbital
>perturbations mentioned in the original article.  

Fine, but that doesn't address the point missed by the original
article, which is that you don't need to precompute this stuff.
It's easy to compute in real time (under a second) which
eliminates the perturbations issue.  You don't need to worry
about inability to predict those if you're not predicting but
rather measuring/correcting in real time.

 paul

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