[ntp:questions] Re: Good GPS for attic?

Danny Mayer mayer at gis.net
Mon Feb 14 06:00:30 UTC 2005

At 09:00 PM 2/12/2005, David L. Mills wrote:
>You are too kind. Fact is, one of the dirty rotten things that cannot be 
>totally resolved is errors due to systematic delay differences on the 
>outbound and return legs. I have a dusty old dissertation here that proves 
>that beyond a shadow. Even with a mesh of interlocking servers, there is 
>always one less equation than necessary for a deterministic solution. 
>However, you can, and the huff-'n-puff filter does, compensate for highly 
>assymetric dalays if there is some time during the day/night when the 
>delays are substantially equal.

True enough. I was merely pointing out that it was a day 1 design
consideration rather than an afterthought or not considered at all.


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