@RichardC10 Thanks again for publishing a detailed explanation about this very interesting stuff.
And yes, questions, as suspected by mm43...
- I buy your "shorter" data consideration, but then how to explain that one negative value was stored if the height of the nominal terminal was chosen high enough to "forbid" negative values (the fact it was perhaps a corrupted data can't make "space" for the sign if not anticipated)?
- IMHO, I don't think that the localization of the nominal terminal can improve the accuracy: when the aircraft is in the area under under the satellite, any incertitude about the time gives a very high incertitude about the position: it is not like there was a physical mirror (for the signal) in this place. You can't use a "percentage incertitude" when subtracting the time of the known legs from the "total" time: you have to use the absolute incertitude.