Where is the GPS receiver located? I see 3 dots where the infared is...

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Level 1

8 points

Where is the GPS receiver located? I see 3 dots where the infared is...

Where is the GPS receiver located on the new iPhone 3G? I see 3 dots where the infared sensor is by the handset speaker... Is there an actual receiver? Why can't I find any real tech specs on the subject?

Can anyone point me in the right direction to learn more?

Alienware M9750, Windows XP, I wish I could buy Leopard for this laptop :(

Posted on Jul 19, 2008 1:03 PM

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Answer 1

demon646 Author

Level 1

8 points

Jul 19, 2008 8:22 PM in response to Dibbler

I see.. I think I can see it when you hold the iPhone in the sunlight.

I needed to know this info because my friend thought that there was no ACTUAL gps receiver in the the iPhone... just the tower triangulation. I had to prove him wrong 😀

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Answer 2

demon646 Author

Level 1

8 points

Jul 19, 2008 9:07 PM in response to greenwr

yeah.. I took a piece of paper and covered the 2 closer to the center and it turned the screen off during a call.. The third one to the left, did not turn it off. I'm thinking that one is the GPS receiver. Anyone know for sure?

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Answer 3

Jul 19, 2008 10:57 PM in response to demon646

None of the 3 "dots" you see are infared or GPS, 2 are proximity sensors that turn the phone off when you hold it next to your face. The other is a light sensor that dims/brightens the screen. The iphone does not have an infared port.

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Answer 4

demon646 Author

Level 1

8 points

Jul 21, 2008 11:26 AM in response to HarleyV05

Ahhh.. Sorry, I was under the impression that proximity switches/detectors WERE infrared as stated here:

http://en.wikipedia.org/wiki/Proximity_detector

"there are many types of proximity detector. common are (1) magnetic proximity switch (2) infrared proximity switch"

I didn't mean to call them infrared because they transmit or received data... but thanks for the clarification. I wasn't aware of the 'magnetic' type of detector.

So... I guess all this means that my original question was not really answered. Is there a REAL GPS receiver that gets info from REAL satellites?

MobileDev gave me a link to here:
http://blogs.zdnet.com/hardware/?p=2261&page=2
that explains, "either from satellites of A-GPS data based on information received from cellphone towers". Does this mean that the iPhone itself does NOT get info directly from satellites?

Message was edited by: demon646

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Answer 5

Jul 21, 2008 11:30 AM in response to demon646

demon646 wrote:
So... I guess all this means that my original question was not really answered. Is there a REAL GPS receiver that gets info from REAL satellites?..."either from satellites of A-GPS data based on information received from cellphone towers". Does this mean that the iPhone itself does NOT get info directly from satellites?

Yes, there is a REAL GPS receiver that communicates with REAL satellites. The "assistance" of A-GPS merely enables that receiver to get a fix on the necessary 3 satellites more rapidly by using data from the cell network (for example, my iPhone 3G gets a fix in a few seconds, my Garmin takes up to a minute), and to compensate when only 2 of the necessary 3 satellites are in view. If no satellites are in view (e.g. if you're inside a building), the cell-tower triangulation can give a rough fix (which shows up as a big location circle when you find yourself on in the Maps app).

Note that the original iPhone did not have a GPS receiver. Only the iPhone 3G has one. That may be the source of some of the confusion, since on the original iPhone, the Maps app uses only cell tower and WiFi data for localization.

Hopefully, this answers your original question. 🙂

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Answer 6

demon646 Author

Level 1

8 points

Jul 21, 2008 12:39 PM in response to neuroanatomist

neuroanatomist wrote:
Yes, there is a REAL GPS receiver that communicates with REAL satellites.

That answers 'most' of it 😀 I did want to know that the new iPhone 3G ACTUALLY gets info directly from satellites (not just relayed from towers).

I also wanted to know where it was located... But I'm thinking now that it is internal and can not be seen from the outside. Is this possible? does GPS info from satellites go through the shell of the phone to an internal receiver?

I did some tests myself to see what the small 'dots' did near the 'ear' speaker did. Here is a pic of what I came up with after using a flashlight while covering some up with electrical tape:
http://slowdemon.com/images/iphone/nogps.jpg

Now, here are pictures from the links above saying that the receiver is located near those sensors (not my pics.. i stole them from the links/websites above):
http://slowdemon.com/images/iphone/iphone3g_gps_antlocation.jpg
http://slowdemon.com/images/iphone/iphonegps_01sm.jpg
Can someone clarify weather or not the GPS antenna is internal and can NOT be seen from the outside of the iPhone 3G?

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Answer 7

Jul 21, 2008 12:43 PM in response to demon646

The GPS antenna is internal, and cannot be seen from the outside. The 'dots' are proximity detectors (two of them) and an ambient light sensor. You can stop experimenting with tape. 😉

Yes, the signal penetrates the plastic case. My Garmin GPS has a 'flip-up' antenna, but that antenna is entirely encased in plastic.

Don't base anything on the proximity of the internal antenna to the external sensors for proximity/light. It's just a coincidence. My hat is near my eyes and brain, but doesn't have any direct relationship to my thoughts (note that I'm not talking about a foil hat here - we all know about the influence there...).

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Answer 8

MobileDev

Level 3

565 points

Jul 19, 2008 2:24 PM in response to demon646

There's a picture of the antenna here:

[Look for the circle with 6 on it|http://blogs.zdnet.com/hardware/?p=2261&page=2]

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Answer 9

Dibbler

Level 2

490 points

Jul 19, 2008 1:07 PM in response to demon646

The GPS chip itself is actually in the upper left corner (sort of next to the decrease volume switch).

Out of interest why do you need to know this?

Dib.

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