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Posts: 130 | Thanked: 13 times | Joined on Dec 2007
#11
It isn't.

I thought the A-GPS on the N95 pointed to Nokia servers somewhere and so needed an internet connection, not a gsm connectuon (other than for the internet). Used to download sat. info, I assume.

Perhaps someone with an N95 can disable the phone, enable WiFi and see if it helps.

If you need to use the cellphone location info, then I agree it gets more complicated.

Zuber
 
Posts: 130 | Thanked: 13 times | Joined on Nov 2005
#12
the Global Position System (GPS) consists of 24 earth-orbiting satellites, the satellites are not in geosynchronous or geostationary orbits and generally you can see no more than 12. and perhaps as few as four. though sirfstariii can receive weak signals and perhaps see several satellites even while buried on your cellar, only 4 or 5 satellites are necessary for an accurate fix. and because houses tend to move very slowly they don't tend to benefit much from gps navigation devices. when the n810 is placed on the dashboard of a car or carried around outside it will probably work just fine.

taking 3 or more minutes for a satellite fix is a long time. my blue tooth gps receiver from nokia seems to take about 30 seconds, but it is usually on; because the battery life is excellent i rarely turn it off.

though the nokia receiver will get an accurate location fix from the cellar of our two story wood frame house, i notice it needs to be very close to a window when i use it in an airplane. (wow, 537 mph at 37,000 feet).

by the way, here's an interesting article on gps and relativity:
http://tinyurl.com/3yo9yt

john
 

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Posts: 874 | Thanked: 316 times | Joined on Jun 2007 @ London UK
#13
There is hope for a speedier SiRF fix
http://www.trustedreviews.com/mobile...-Technology/p1
 
Posts: 130 | Thanked: 13 times | Joined on Dec 2007
#14
The site says something about "By not requiring any network connectivity or downloads, it significantly improves the daily navigation experience for consumers of mobile navigation devices."

So I think that suggests AGPS using downloads from the internet would be possible for the N810.

Still like to know where best to suggest it though. Would this be a Nokia thing a Maemo thing or is it all the same...

Zuber
 
Posts: 17 | Thanked: 0 times | Joined on Nov 2007
#15
Originally Posted by Zuber View Post
So I think that suggests AGPS using downloads from the internet would be possible for the N810.
http://en.wikipedia.org/wiki/Assisted_GPS
 
Posts: 164 | Thanked: 132 times | Joined on Dec 2007
#16
Originally Posted by jdr93 View Post
the Global Position System (GPS) consists of 24 earth-orbiting satellites, the satellites are not in geosynchronous or geostationary orbits and generally you can see no more than 12. and perhaps as few as four.
There are actually 31 GPS satellites right now, and the number is growing every year.

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

Some satellites are in fact in geosynchronous orbits, such as #35, #47, #48, and #51. N810 doesn't see those as it doesn't support WAAS.
 
Posts: 41 | Thanked: 3 times | Joined on Oct 2007
#17
Weird that ajax1's opinion of the GPS is completely different (except for the "maybe doing a cold start every time" bit). I'm not saying either one of you is wrong, just that there seems to be a wide range in opinion on the GPS performance.

ag2 suggests that the chip is not a SiRFIII but a low-cost TI GPS5300 like that found in the N95/E90. This is believable (if disappointing) because Nokia probably has a big bucket of them sitting around their assembly plant, but I didn't think gpsd supported this chip yet. Perhaps Nokia wrote their own driver...

Seems to me that if chip is a SiRFIII then the "problems" people are seeing are probably software (or antenna) and possibly solvable. If it's a GPS5300 then I'll just buy a Holux to wire into my car. Are there any online sites that opened up their N810's (a la Ars' vivisection reviews) so we can peek at the GPS chip markings?
 
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Posts: 716 | Thanked: 236 times | Joined on Dec 2007
#18
It is a TI (I forgot who/how, but there are threads). /usr/sbin/gpsdriver translates the serial data (/dev/ttyS0? or is it /dev/pgps) into a NMEA stream on a pseudo-tty. gpsd is launched and on port 2947 works (as far as I checked) like the standard linux one.

Port 2947 is apparently local (lo/127.0.0.1) only but with proxy software (e.g. socat) you can send it to another computer.

The internal GPS apparently does NOT have WAAS or EGNOS to improve accuracy.

My short answer is if you don't just need GPS casually or infrequently, get a BT GPS (I have a G[lobal] Top G33, $49 incl shipping from buygpsnow - 5Hz; the G66 is a thinner version, and there is a HUD speed/direction version).

Even if they were to get a better chipset, they could not stuff an adequate antenna in there. I already have an external BT keyboard, a BT headset, and other extensions.

The internal GPS is like the internal keyboard - good for something quick, but not for advanced usage. Or the speakers - they work but aren't going to do justice to music. They've made it very easy to extend using a BT GPS, and they aren't that expensive.

Though I do appreciate the internal GPS as I don't always have my BT version with me.
 
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Posts: 213 | Thanked: 27 times | Joined on Oct 2007 @ Detroit, MI
#19
i have an iBlue 737 and it works flawlessly.
 
Posts: 130 | Thanked: 13 times | Joined on Dec 2007
#20
Originally Posted by tz1 View Post
It is a TI My short answer is if you don't just need GPS casually or infrequently, get a BT GPS.
To be honest, though I find the couple of minutes delay that you sometimes get in obtaining a lock annoying, other than that the internal GPS has performed fine for me so far.

Maybe I will run into trouble if I enter some high building areas while using it, I don't know.

But on all the runs I've used it for so far (hundereds of miles), it's been fine.

Just the initial lock time that is a problem. Hence my wanting A-GPS.

I do actually already have an external bluetooth unit, so not being tight or anything. Just don't find it worth the agro.

Might take it with me if I go on a hike some time. Perhaps being in the middle of a deep valley or something could affect the signal, but for the kind of stuff I do, I doubt it.

Reading through the A-GPS notes in the wiki, I still think that the N810 could benefit from it. Not sure if there would be a way of using the cellphone data through bluetooth, but it looks to me like a number of points mentioned would apply.

So back to my orig. question. Who/where does one go to request this enhancement. Nokia site, Meamo site ?

To be honest, having followed the N95, Nokia should be fairly upto speed by now about people complaining about slow lock times.

Thanks,

Zuber
 
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