Re: [gpsd-dev] gpsd - AT command control on modems

[Gary E. Miller]

Yo Paul!

On Sun, 14 Jul 2019 09:36:22 +0300
Paul Fertser <address@hidden> wrote:

> Hey Gary,
> 
> On Sat, Jul 13, 2019 at 05:08:31PM -0700, Gary E. Miller wrote:
> > > sorry for not replying earlier but I didn't get your reply (or
> > > any of the other replies here) into my inbox, so I just now
> > > accidentally saw in the webinterface that there have been
> > > replies. I'm not subscribed to the list, so maybe you used
> > > "Reply" instead of "Reply all" ?  
> > 
> > I don't do private consults, except to paying clients.  So all
> > my replies will be on the list.  And that way other people can
> > also help.  
> 
> It's not about private consulting, it's about keeping the Cc list
> intact, that is, when replying to messages in public one is supposed
> to be using "Group reply"/"Reply all", this way neither the list is
> omitted nor the person you reply to, nor all the others who might have
> been in the Cc list already but not subscribed to the particular
> mailing list. I mean, Luca is talking about the most common regular
> way of using mailing lists, nothing special about it.

That is not the policy of this list.  Or any other list I am on.
Reply All has long been discouraged here.  Last time we stopped
it was because of the echo storms it caused.


> > No modern GPS needs assistance data.  That just speeds up the
> > start, which for a new GPS should still be under 2 minutes.  
> 
> I would speculate assistance data can help a lot when the reception
> conditions are too poor (EMI, physical obstacles) for reliable
> reception of ephemeris from the sats but good enough to be getting
> time signal from them. Am I wrong here?

Here we prefer data and experience to speculation.

A modern GPS will just listen to all GPS at once on startup.  If there
is a strong enough signal then the ephemeris for that sat is downloaded
in 90 seconds.  If the signal is not strong enough, then the ephemeris
is useless.

So only GPS with only a few receive channels, mostly older ones, benefit
from assistance data.

This is why the more modern GPS no longer even support assistance data.

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

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    "If you can’t measure it, you can’t improve it." - Lord Kelvin

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