[IGSMAIL-6275] Re: Tranformation parametres between IGS reference frames realizations

[Stefano Ferri]

Thank you all, and please excuse me for this late reply.

I did't notice the "repro1" folder with the reprocessed time series. I 
began my analysis in January, and I knew that reprocessing was in 
progress, but I missed the IGS mail you mentioned in your message, and I 
thought that these products still were not available.
I will use these new data instead of doing Helmert transformation, of 
course. Thank you.

Best regards,
Stefano Ferri






Il 26/09/10 14.56, jim.ray at noaa.gov ha scritto:
> Author: Jim Ray, IGS Analysis Center Coordinator (ACC)
>
> Dear Stefano,
>
> IGS Mail is not the best forum for general user questions.  However,
> since your question is one of importance to many people, please let
> me give some guidance (though hopefully most subscribers know these
> things already).
>
> At the ACC website -- http://acc.igs.org/ -- information about dealing
> with past frame changes is given under the "SP3 Satellite Files" heading.
> However, more recently, better advice for nearly all users is to use the
> IGS reprocessed ("repro1") products.  Information about the release of
> these products last April is given under "General Information" at the
> ACC site or directly in the email message at:
>
>    http://igscb.jpl.nasa.gov/mail/igsmail/2010/msg00084.html
>
> Essentially, the new consistently reprocessed product files are in the
> usual CDDIS product directories but in the lower "repro1" subdirectories.
> The IGS05 frame (aligned to ITRF2005 but with relative ->  absolute
> antenna calibration corrections applied) is used throughout.
>
> All the necessary background and evaluation information is given at
> the repro1 website:  http://acc.igs.org/reprocess.html .
>
> Hope this satisfies your needs.
>
> --Jim
>
>
>
> ----- Original Message -----
> From: Stefano Ferri<stefano.ferri9 at unibo.it>
> Date: Sunday, September 26, 2010 8:41 am
> Subject: [IGSMAIL-6272] Tranformation parametres between IGS reference	frames realizations
> To: "igsmail at igscb.jpl.nasa.gov"<igsmail at igscb.jpl.nasa.gov>
>
>> Dear list,
>>
>> I've just subscribed to IGSmail in the hope to solve a problem.
>>
>> I'm analyzing the time series of some IGS stations. Since the time
>> interval spans from 1999 to 2009, I have 3 reference frame to dial
>> with: IGS97, IGS00 and IGS05. I need to remove the jumps due to those
>> reference frame changes, and I would like to transform all in the IGS05.
>> Therefore, looking on the ITRF website, I've found some documentation
>> here:
>>
>>
>>
>> where  transformation parameters between all the ITRF reference frames
>> are reported. These are not parametes between IGS reference frames,
>> but since I've not found them, I've tryed anyway. After the Helmert
>> transformation, I've converted cartesian coordinates into North, East
>> and Up components. While North and East were succesfully corrected,
>> the Up component shows a jump 2006, and a smaller one in 2001,  when
>> there were the switches from IGS97 to IGS00 and from IGS00 to IGS05.
>>
>> Since I've not found transformations parameters between IGS
>> realization, but only between ITRFs, I would like to know if there is
>> a webpage or some documents repporting the official parameters. IGS'
>> are aligned to ITRFs, but is it correct to use the parameters reported
>> in the ITRF website for transformations between IGS realizations of
>> the ITRF? Is there something like IERS' technical notes containing
>> IGS-related informations?
>> Could it be possible that the switch from relative to absolute antenna
>> calibrations causes the jump in the Up component? If so, how to
>> estimate it?
>>
>>
>> Thank you in advance for any reply.
>>
>> Best regards,
>> Stefano Ferri
>>
>>
>> --
>> Stefano Ferri
>> Department of Physics - Sector of Geophysics
>> University of Bologna
>> Viale Berti Pichat 8, 40127 Bologna - Italy
>> Tel. +39 051 2095066
>> Fax  +39 051 2095058
>> _______________________________________________
>> IGSMail mailing list
>> IGSMail at igscb.jpl.nasa.gov
>>


-- 
Stefano Ferri
Department of Physics - Sector of Geophysics
University of Bologna
Viale Berti Pichat 8, 40127 Bologna - Italy
Tel. +39 051 2095066
Fax  +39 051 2095058