[time-nuts] GPS position averaging

[Jim Lux]

On 12/15/14, 5:35 PM, Bob Camp wrote:
> Hi
>
>> On Dec 15, 2014, at 8:29 PM, Paul <tic-toc at bodosom.net> wrote:
>>
>> On Mon, Dec 15, 2014 at 6:39 PM, Angus <not.again at btinternet.com> wrote:
>>
>>> But is it the closest to the 'true' position that you really want, or
>>> the best estimate of where the particular GPS you are testing thinks
>>> it is?
>>>
>>
>> I don't understand what you're saying here.  Can you phrase it differently?
>
>
> I proposed two possible solutions to the problem:
>
> 1) Do the long term average with your specific GPS gizmo.
>
> 2) Get a survey grade GPS in and determine the “real” location.
>
> The NIST papers do indicate that #1 does not equal #2 for the gear they tested.
>
> So the question - If they are not going to be equal, which one do you pick?
>
>

if you've got observables and they're in RINEX format, you can do 
offline processing through JPL's GIPSY thing..

If you're looking at data that's a week old, they've had plenty of time 
to process all the observed satellite behavior, calculate ionospheric 
corrections, changes in earth's rotation due to earthquakes and 
tsunamis, and all that sort of stuff.

http://apps.gdgps.net/

Oddly, the picture of the guy on the cellphone in the left side of the 
banner looks like Yoaz Bar-Sever, who runs the gdgps stuff.

Why he's on a phone, I'm not sure.. apps is more of a file/web sort of 
thing.