[time-nuts] iGPS?

[Tim Shoppa]

The parts of the iGPS story that I actually understand, make it sound like
it will decrease acquisition time and especially decrease acquisition time
in presence of jamming. Like how cellphone tower fixes can give a
cellphone's GPS an initial guess at time/position and speed up GPS
acquisition (aka aGPS).

As cellphones move more towards wifi and away from traditional cellphone
technologies, the initial Iridium fix may become more important.

My grasp above, has nothing to do with "orders of magnitude" more precision
in a fix. But I could see at least an order of magnitude or more in faster
acquisition, as compared to a complete cold start.

Tim N3QE


On Sun, May 17, 2015 at 10:10 PM, Bob Camp <kb8tq at n1k.org> wrote:

> Hi
>
> “Orders of magnitude” more accurate …
>
> Right now, you can get around ~1 M in most areas. One order of magnitude
> would be <10 cm.
> More than one order of magnitude would be <10 mm. To me “orders” implies
> more than two, so that
> would be <1 mm.
>
> I guess everybody can toss out all their multi band GPS gear, there’s no
> need for it anymore.  No need
> to put up all those expensive block III GPS sat’s either :)
>
> hmmmmm……I do believe the marketing boys have been playing with the
> numbers. You would have to start
> from a >50 M error to get them to make much sense based on what they are
> doing.
>
> ===========
>
> If you dig a bit more, Apple bought Coherent Navigation almost a half year
> ago. The main purpose appears
> to be merging their mapping software into Apple’s ill-fated maps program.
> Given that Iridium is a “pay’
> service (as in $$$$$) you probably will not see it in run of the mill cell
> phones very soon ….
>
> Bob
>
> > On May 17, 2015, at 7:07 PM, Chris Albertson <albertson.chris at gmail.com>
> wrote:
> >
> > Anyone know anything about "iGPS"?  Apparently the Iridium low orbit
> > communications sats are now modified via software update to send
> > signals that when combined with GPS allow for a receiver that is MUCH
> > more precise and harder to jam and can work in urban areas better.
> > Apple just bought a company that is building iGPS receivers.   Looks
> > like something that they might want to put inside a cell phone but
> > when you have an orders of magnitude important in position you'd
> > expect better timing too, or so I would think.
> >
> > Seems like a very smart idea if all that was required was a software
> > upload to existing spacecraft.  From what I read this is real, not a
> > proposal another are real receivers being tested.
> >
> >
> > --
> >
> > Chris Albertson
> > Redondo Beach, California
> > _______________________________________________
> > time-nuts mailing list -- time-nuts at febo.com
> > To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> > and follow the instructions there.
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>