Bruce in alaska wrote:
and ignores the surface effect that allows UK TV& VHF signals to be
picked up as far away as in the Netherlands.

Horizontal Bending doesn't work all that well at 1.6 Ghz, and is
negligible, in its effect. Temperature Inversion Refraction is also
negliable at 1.6 Ghz, and even if you could count on any specific
Inversion System to be present at any one time. Both of the above are
present for frequencies below 1 Ghz, and could contribute a small effect
but above 1 Ghz, it just isn't going to happen....

I'd be willing to trust you one this (I have been a ham since 1977,
la8nw), but we are after all in a sat-nav newsgroup he

Why do we talk about pseudo-range measurements and corrections? Isn't
this due to bending of signals at 1.575 GHz?

OTOH, as long as the effect is in the sub-percent range, it really
doesn't matter when we're discussing 1.2 vs 1.0 rule-of-thumb factors. :-)

Terje
--
- Terje.Mathisen at tmsw.no
"almost all programming can be viewed as an exercise in caching"