this summer the Russian mobile company MTS has launched a GLONASS savvy
smartphone, called MTS Glonass 945. It also handles GPS.

Now apparently Apple is the first non-Russian company to use Glonass in a
smartphone: the iPhone 4S.
See the specs: http://www.apple.com/iphone/specs.html (scroll down quarter
page)

I guess this will make the iPhone 4S better at handling urban canyons, also
accuracy should be improved with about 50 birds available in total.

Does anybody know how much improvement to expect in accuracy?

Vincent

On 2011-10-19 17:36 , Vincent van der Laan wrote:
> this summer the Russian mobile company MTS has launched a GLONASS savvy
> smartphone, called MTS Glonass 945. It also handles GPS.
>
> Now apparently Apple is the first non-Russian company to use Glonass in a
> smartphone: the iPhone 4S.
> See the specs: http://www.apple.com/iphone/specs.html (scroll down quarter
> page)
>
> I guess this will make the iPhone 4S better at handling urban canyons, also
> accuracy should be improved with about 50 birds available in total.
>
> Does anybody know how much improvement to expect in accuracy?

I would say not much.

I've recorded tracks with the iPhone 4 (not S) and a separate receivers.

The separate receivers set at 1 Hz and 0.2 Hz (once every 5 seconds)
recorded very smooth tracks. When "marked" to identify landmarks (tip
of a boulevard separator for example) the error was often less than 2
meters and typically less than 5.

With the iPhone 4, the track was erratic with long intervals (2 or more
seconds) between points. Position error was over 5 meters and typically
over 10 meters.

Why? The iPhone 4 GPS samples slowly to conserve power. I doubt this
is different with the GLONASS ability though the additional range info
_should_ help in canyons (urban and otherwise) as you point out and
probably in the woods.

But I don't think it will improve accuracy overall very much - that
requires continuous tracking to maintain a smoother range set.

Thanks for pointing out that it uses GLONASS as well as GPS.

--
gmail originated posts filtered due to spam.

On 19 Ott, 23:36, Vincent van der Laan <vinc...@allalin.nl> wrote:
> this summer the Russian mobile company MTS has launched a GLONASS savvy
> smartphone, called MTS Glonass 945. It also handles GPS.
>
> Now apparently Apple is the first non-Russian company to use Glonass in a
> smartphone: the iPhone 4S.
> See the specs:http://www.apple.com/iphone/specs.html(scroll down quarter
> page)
>
> I guess this will make the iPhone 4S better at handling urban canyons, also
> accuracy should be improved with about 50 birds available in total.
>
> Does anybody know how much improvement to expect in accuracy?

In accuracy, I think not much... if you are in open sky
But there is a big improvement in satellites availability that will
certainly help in difficult reception conditions.
Taking into account the only Glonass (they may have improved other
parts: antenna, chipset, RF... ecc making the iPhone4S much better,
but not only because of Glonass)