IPhone 4S has GLONASS in addition to GPS

Re:IPhone 4S has GLONASS in addition to GPS by flipbrad on Wednesday October 19, 2011 @08:25AM (#3129794)

I'm wondering whether it actually matters to people whether their GPS device has 2, 4 or 7m accuracy. Anything with lower resolution than about 5 cm is going to be largely useless for robotic driving, etc, particularly anything worse than 2 m res - so really (and not meaning to be rude to you and your research efforts) - isn't the different resolution irrelevant, and isn't the only reason GPS users should be happy about GLONASS integration is redundancy (especially in the rare military event that the US decides to switch public GPS off?)

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Re:IPhone 4S has GLONASS in addition to GPS by jws on Wednesday October 19, 2011 @08:37AM (#3129841)

Computer driving is more about vision systems than GPS. Maps certainly aren't accurate into the centimeter range in any event.

Sailors find that their charts are some times off by kilometers. I've personally seen a large, erroneous discontinuity in the western coast of St. Lucia while using a GPS chart plotter for navigation. Chart data is copied forward from older charts, many of which were made in the 1800s, those guys were good with a sextant, chronometer, and a pen, but when near land you need your eyeballs.

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Re:IPhone 4S has GLONASS in addition to GPS by ChuckMcM on Wednesday October 19, 2011 @03:16PM (#3131612)

If your maps were wrong you could start a war :-) [1]

[1] http://abcnews.go.com/blogs/politics/2010/11/google-nearly-s...

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Re:IPhone 4S has GLONASS in addition to GPS by FrojoS on Wednesday October 19, 2011 @10:46AM (#3130356)

Wow. Shouldn't it be strate forward to correct such large errors by using public available satellite images?

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Re:IPhone 4S has GLONASS in addition to GPS by aw3c2 on Wednesday October 19, 2011 @08:28AM (#3129808)

Think of augmented reality apps, 2 vs 7 meters can be a big difference here if you are close to the "to be augmented" target.

Also for OpenStreetMap this would be great. This would get the accuracy down to "error less wide than a street" levels on customer devices.

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Re:IPhone 4S has GLONASS in addition to GPS by zb on Wednesday October 19, 2011 @09:43AM (#3130069)

It means more satellites in the constellation(s), and in circumstances where that makes the difference between getting a GPS/GLONASS fix and having to rely on cell tower/WiFi positioning then the difference in accuracy would be very significant.

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Re:IPhone 4S has GLONASS in addition to GPS by flipbrad on Wednesday October 19, 2011 @01:58PM (#3131256)

Isn't that point confirming what I said, albeit confusing redundancy (availability of other systems as backup when GPS fails) with accuracy?

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Re:IPhone 4S has GLONASS in addition to GPS by zb on Wednesday October 19, 2011 @02:40PM (#3131448)

I'm not talking about the entire system failing and falling over to the other, I'm talking about the probability that from any given point you can see enough satellites to get a fix. More satellites is better.

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Re:IPhone 4S has GLONASS in addition to GPS by natch on Wednesday October 19, 2011 @12:00PM (#3130713)

I would love it if I could use "find my iPhone" inside my house without having to resort to the audible alert when other people are sleeping. So, yes, better resolution would be wonderful. Edit: and to address the obvious objection, no, the current resolution is not good enough for this. With the current accuracy, I'm not able to locate my phone within my house yet (iPhone 4, and no canyon issues here).

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Re:IPhone 4S has GLONASS in addition to GPS by Tloewald on Wednesday October 19, 2011 @08:42AM (#3129855)

Anyone tested iPhone navigation in a gps blackout area (e.g. Near an air force base?). I used to live in Lompoc and GPS wouldn't work in most of the town owing to the proximity of Vandenberg AFB.

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Re:IPhone 4S has GLONASS in addition to GPS by georgecmu on Wednesday October 19, 2011 @01:26PM (#3131117)

I wasn't aware there of existence GPS blackout areas anywhere, esp. in the continental United States. Do you have more information that would support your statement?

For what it's worth, GPS seems to work fine for a lot of people around Lompoc, CA: http://www.strava.com/rides-by-country/united-states/califor...

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Re:IPhone 4S has GLONASS in addition to GPS by Tloewald on Thursday October 20, 2011 @09:41AM (#3134752)

The evidence is personal experience. The blackout only affects a certain radius of Vandenberg which only covers a part of Lompoc.

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Re:IPhone 4S has GLONASS in addition to GPS by georgecmu on Thursday October 20, 2011 @02:59PM (#3136331)

So, what exactly happens there? Your device stops seeing satellites (loses lock)? Or does the reported uncertainty become on the order of hundreds of meters? Or does it simply give you confused directions when you're driving?

Searching for combinations of terms like "GPS, blackout, airforce base, lompoc" only brings up this thread. I find it hard to believe that if it were a real occurrence no one else would notice and write/complain about it.

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Re:IPhone 4S has GLONASS in addition to GPS by omgtehlion on Wednesday October 19, 2011 @08:59AM (#3129917)

GLONASS uses nearly the same frequency range as GPS, so the answer is no.

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Re:IPhone 4S has GLONASS in addition to GPS by huhtenberg on Wednesday October 19, 2011 @10:06AM (#3130175)

Tangentially related - IIRC GLONASS also happens to have an almost identical frame structure to GPS. Very peculiar fact given the context.

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