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Posted by Paul Cooper on June 5, 2007, 3:59 pm
Please log in for more thread options On Tue, 05 Jun 2007 15:17:15 -0000, Marc Pelletier
>
>> This is not needed and hasn't been since the constellation was
>> completed. In open country, as far as I am aware there are no
>> preferrred times; you will always have enough satellites above the
>> horizon and sufficiently widely spaced for a good fix. This is a
>> historic problem dating back to the days before the constellation was
>> complete, but it simply isn't a problem these days.
>>
>
>Actually I was surprised to find this wasn't so just recently. In Feb of
>this year we were working in Newfoundland, Canada and frequently had only 4
>satellites in view above a 10° mask angle. Lowering the mask gave a better
>but noisier result. We had a fix, but certainly not a good one. I'm
>guessing that there were one or more satellites removed from service for
>some reason, because this really is rare nowadays.
>
>cheers
>
>Marc Pelletier
I'm surprised too - we work in Antarctica, and for the last few years
we haven't even bothered checking satellite ephemera; we always get a
post-processed result better than a centimetre anyway useing
auto-Gypsy.
Paul
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