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IPhone 4S has GLONASS in addition to GPS

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Re: IPhone 4S has GLONASS in addition to GPS

#4

Post by mhw »

dchest wrote: post #2

Precisions: * GPS: 2.00—8.76 m * GLONASS: 4.46—7.38 m * GPS+GLONASS: 2.37—4.65 m [citation needed] (source: http://en.wikipedia.org/wiki/GLONASS ).

From which:

    To improve development of the user segment, on August 11, 2010, Sergei Ivanov
    announced a plan to introduce a 25% import duty on all GPS-capable devices,
    including mobile phones, unless they are compatible with GLONASS.
I think I can see why the GPS chipsets are starting to adopt this...

Re: IPhone 4S has GLONASS in addition to GPS

#6

Post by singular »

dchest wrote: post #2

Precisions: * GPS: 2.00—8.76 m * GLONASS: 4.46—7.38 m * GPS+GLONASS: 2.37—4.65 m [citation needed] (source: http://en.wikipedia.org/wiki/GLONASS ).

though off-topic and a bit of an aside, at university (I did civ eng) I learnt that it was possible to get cm-levels of accuracy out of GPS through clever arrangement of multiple sensors (for e.g. measuring the movement of buildings due to subsidence, etc.)

In fact I just found a wikipedia article all about it - http://en.wikipedia.org/wiki/GPS_augmentation :)

Re: IPhone 4S has GLONASS in addition to GPS

#7

Post by nodata »

singular wrote: post #6
dchest wrote: post #2

Precisions: * GPS: 2.00—8.76 m * GLONASS: 4.46—7.38 m * GPS+GLONASS: 2.37—4.65 m [citation needed] (source: http://en.wikipedia.org/wiki/GLONASS ).

though off-topic and a bit of an aside, at university (I did civ eng) I learnt that it was possible to get cm-levels of accuracy out of GPS through clever arrangement of multiple sensors (for e.g. measuring the movement of buildings due to subsidence, etc.) In fact I just found a wikipedia article all about it - http://en.wikipedia.org/wiki/GPS_augmentation :)

They use this on automated farms. At known co-ordinates, they stick a GPS receiver in the ground. The difference between the known co-ordinates and what that GPS receiver sees is then continuously transmitted to the vehicles on the farm.

Re: IPhone 4S has GLONASS in addition to GPS

#8

Post by mikepurvis »

nodata wrote: post #7
singular wrote: post #6

Earlier quoted context omitted.

though off-topic and a bit of an aside, at university (I did civ eng) I learnt that it was possible to get cm-levels of accuracy out of GPS through clever arrangement of multiple sensors (for e.g. measuring the movement of buildings due to subsidence, etc.) In fact I just found a wikipedia article all about it - http://en.wikipedia.org/wiki/GPS_augmentation :)

They use this on automated farms. At known co-ordinates, they stick a GPS receiver in the ground. The difference between the known co-ordinates and what that GPS receiver sees is then continuously transmitted to the vehicles on the farm.

It's called rtk correction: http://en.wikipedia.org/wiki/Real_Time_Kinematic

There's an opensource rtklib which supports a handful of inexpensive receivers: http://gpspp.sakura.ne.jp/rtklib/rtklib.htm

Re: IPhone 4S has GLONASS in addition to GPS

#9

Post by hackermom »

Related: the two first Galileo satellites (http://en.wikipedia.org/wiki/Galileo_(satellite_navigation)) will be launched tomorrow. The claimed precision of the free-for-all service is as granular as 1 meter, with the military/commercial service claiming to reach centimeter precision. I wonder when this shows up in smartphones.
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