Re: ✘Here comes North American Terrestrial Reference Frame of 2022 (NATRF2022)

[Gary E. Miller]

Yo Greg!

On Thu, 03 Feb 2022 09:50:21 -0500
Greg Troxel <gdt@lexort.com> wrote:

> And, I am not aware of gpsd dealing with datum,

If the GNSS receiver is only sending ECEF coordinates, then gpsd will
calculate lat/lon/alt and magnetic variation using wmm2015. EGM2008.and
WMM2015.

gpsd/geoid.c

Some of that comes from a precalculated grid of valuse from the geographiclib
package.  I have toyed with allowing gpsd to inegrate more directly with
that package.

> and while this should all have datum tags, it doesn't seem to in
> practice.

And the more modern datums have time varying companents, so you also
need to know the date that the firmware used for it internal
tables.

> I think we will be able to avoid dealing with those questions for
> several years, at least those of us that don't work in those agencies.

We already worry about 2038 rollover, this will be sooner.  BUt, as you said,
hardly anyone will really notice the small changes.

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        gem@rellim.com  Tel:+1 541 382 8588

            Veritas liberabit vos. -- Quid est veritas?
    "If you can't measure it, you can't improve it." - Lord Kelvin

pgpd5WYi8bTNA.pgp
Description: OpenPGP digital signature