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SW

Skip Withrow

Mon, Oct 17, 2022 9:29 PM

Hello time-nuts,
I have been doing some GPS PPP work (mostly with NrCan) and have a question
as to what clock scale the IGS clock products are referenced to?

I would assume that the GPS data is GPS time, which is steered by
UTC(USNO). So, clock solutions that I compute should be corrected by the
difference between USNO and BIPM to get UTC.

What about other satellite constellations? I'm sure IGS keeps track of
them as well. And I'm sure that Galileo, Glonass, and the rest use
different time scales. Do IGS clk files represent the system that they are
reporting, or is there some translation to a common time scale?

I tried doing some research and did not come up with anything definitive.
Any pointers in the correct direction would be appreciated.

Thanks,
Skip Withrow

Hello time-nuts, I have been doing some GPS PPP work (mostly with NrCan) and have a question as to what clock scale the IGS clock products are referenced to? I would assume that the GPS data is GPS time, which is steered by UTC(USNO). So, clock solutions that I compute should be corrected by the difference between USNO and BIPM to get UTC. What about other satellite constellations? I'm sure IGS keeps track of them as well. And I'm sure that Galileo, Glonass, and the rest use different time scales. Do IGS clk files represent the system that they are reporting, or is there some translation to a common time scale? I tried doing some research and did not come up with anything definitive. Any pointers in the correct direction would be appreciated. Thanks, Skip Withrow

BK

Bob kb8tq

Tue, Oct 18, 2022 1:50 AM

Hi

Galileo time and GPS time are linked about as closely as
you can do and still have two independent systems. Glonass
is synced to the Russian version of UTC ( = UTC(SU) ). Since
that is a component of UTC / BIPM, it does indeed tie in at
some point.

Bob

On Oct 17, 2022, at 5:29 PM, Skip Withrow via time-nuts time-nuts@lists.febo.com wrote:

Hello time-nuts,
I have been doing some GPS PPP work (mostly with NrCan) and have a question
as to what clock scale the IGS clock products are referenced to?

I would assume that the GPS data is GPS time, which is steered by
UTC(USNO). So, clock solutions that I compute should be corrected by the
difference between USNO and BIPM to get UTC.

What about other satellite constellations? I'm sure IGS keeps track of
them as well. And I'm sure that Galileo, Glonass, and the rest use
different time scales. Do IGS clk files represent the system that they are
reporting, or is there some translation to a common time scale?

I tried doing some research and did not come up with anything definitive.
Any pointers in the correct direction would be appreciated.

Thanks,
Skip Withrow

time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe send an email to time-nuts-leave@lists.febo.com

Hi Galileo time and GPS time are linked about as closely as you can do and still have two independent systems. Glonass is synced to the Russian version of UTC ( = UTC(SU) ). Since that is a component of UTC / BIPM, it does indeed tie in at some point. Bob > On Oct 17, 2022, at 5:29 PM, Skip Withrow via time-nuts <time-nuts@lists.febo.com> wrote: > > Hello time-nuts, > I have been doing some GPS PPP work (mostly with NrCan) and have a question > as to what clock scale the IGS clock products are referenced to? > > I would assume that the GPS data is GPS time, which is steered by > UTC(USNO). So, clock solutions that I compute should be corrected by the > difference between USNO and BIPM to get UTC. > > What about other satellite constellations? I'm sure IGS keeps track of > them as well. And I'm sure that Galileo, Glonass, and the rest use > different time scales. Do IGS clk files represent the system that they are > reporting, or is there some translation to a common time scale? > > I tried doing some research and did not come up with anything definitive. > Any pointers in the correct direction would be appreciated. > > Thanks, > Skip Withrow > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com

GR

Gabs Ricalde

Tue, Oct 18, 2022 11:20 AM

That would be the IGS timescale

K. Senior; P. Koppang; J. Ray
Developing an IGS time scale
https://doi.org/10.1109/TUFFC.2003.1209545

K. Senior
Clock Products Working Group
https://www.bipm.org/documents/20126/28434896/working-document-ID-5374/6a470f28-2d57-f5aa-01ce-08d5ff7c7339

On Tue, Oct 18, 2022 at 9:35 AM Skip Withrow via time-nuts
time-nuts@lists.febo.com wrote:

Hello time-nuts,
I have been doing some GPS PPP work (mostly with NrCan) and have a question
as to what clock scale the IGS clock products are referenced to?

I would assume that the GPS data is GPS time, which is steered by
UTC(USNO). So, clock solutions that I compute should be corrected by the
difference between USNO and BIPM to get UTC.

What about other satellite constellations? I'm sure IGS keeps track of
them as well. And I'm sure that Galileo, Glonass, and the rest use
different time scales. Do IGS clk files represent the system that they are
reporting, or is there some translation to a common time scale?

I tried doing some research and did not come up with anything definitive.
Any pointers in the correct direction would be appreciated.

Thanks,
Skip Withrow

time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe send an email to time-nuts-leave@lists.febo.com

That would be the IGS timescale K. Senior; P. Koppang; J. Ray Developing an IGS time scale https://doi.org/10.1109/TUFFC.2003.1209545 K. Senior Clock Products Working Group https://www.bipm.org/documents/20126/28434896/working-document-ID-5374/6a470f28-2d57-f5aa-01ce-08d5ff7c7339 On Tue, Oct 18, 2022 at 9:35 AM Skip Withrow via time-nuts <time-nuts@lists.febo.com> wrote: > > Hello time-nuts, > I have been doing some GPS PPP work (mostly with NrCan) and have a question > as to what clock scale the IGS clock products are referenced to? > > I would assume that the GPS data is GPS time, which is steered by > UTC(USNO). So, clock solutions that I compute should be corrected by the > difference between USNO and BIPM to get UTC. > > What about other satellite constellations? I'm sure IGS keeps track of > them as well. And I'm sure that Galileo, Glonass, and the rest use > different time scales. Do IGS clk files represent the system that they are > reporting, or is there some translation to a common time scale? > > I tried doing some research and did not come up with anything definitive. > Any pointers in the correct direction would be appreciated. > > Thanks, > Skip Withrow > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com

time-nuts@lists.febo.com

What time scale does IGS use to report its clock files?