[Tutorial] Faster A-GPS response on Nokia N9
 

Hi guys!

Today I was trying to change my SUPL server on my Nokia N9, but surprisingly, I cannot do it by Settings. I tried to search on Google, but not found anything about it.
So I started to search where it is configured and change.
Here it is!!

Step 1: Enable developer mode and open Terminal
Step 2: On Terminal type
If you not changed your password yet, it will be "rootme"

Step 3: edit the file below by typing
Inside that file, edit it to be like the one below (in bold the edited strings)

Step 4: save the file using "CTRL X"
Step 5: reboot the phone

From now, your GPS will be 'locked' faster than before!!
In my tests the GPS locked in less than 10 seconds (after Nokia Maps fully loaded)!
Before, the lock was around 40 seconds to 1 minute.

It's known the SUPL Nokia server is slow, and in Brazil (where I live) it's outdated, so the solution is to use Google servers.

I hope it helps! =D

PS: If you not have 'nano' and receive 'not found', install it using command:
PS2: I use "true" to "SuplForced", 'cause I always have internet connection, but if you don't have it, leave it "false". ;)

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

Thanks for this tip. If SuplForced is false, will this mod make the GPS lock faster?

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

Your GPS will lock faster if you use SUPL servers (A-GPS)!

A-GPS use cells informations to triangulate your position, and to get coordinates of the cells it will query SUPL servers... ;)

So the property will be "true" if you wanna ALWAYS use SUPL servers (A-GPS) instead of waiting regular-GPS satellites to respond.

Get it?! :)

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

Not knowing how to change my SUPL server on the N9 was driving me Crazy!! Thanks so much!

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

excellent finding, thanks for sharing!

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

normally when i'm in the car i get a lock very quickly without having this modded... i shall mod and see if there is a noticeable difference

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

Tried to ping supl.nokia.com:
18-20 ms
supl.google.com:
134-256 ms

This was from Sweden. I would say this mods effect will highly depend on your location.

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

Aye, in the US I have the opposite effect.

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

That's what I'm talking about. In Brasil the pings not differ so much, but the Google Database is more accurate and updated... ;)

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

Please, can anybody explain how to edit file with configurations in step 3. I just can't change the code :(

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

I live in pennsylvania in the states. Pinged nokia and got an average of 71ms. Pinged google and got 128ms. Maybe in certain parts of the country is better?

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

Well that's not entrely correct by the facts, though the result will be same.
SUPL (in MSB mode) provides ephemeris and almanac (data about position and trajectory of visible sats etc, needed to calculate your position based on exact sats' position) for the location you're at (+/- a few 100 miles). Usually - without "A"ssited - this data gets downloaded from the GPS sats at a rate of some iirc 50bits per second, taking up to 12:30minutes for one complete set of data to transfer - if you have no reception dropouts during that time.
To get your initial position to request for the right data set, your phone uses different sources like last known position, CountryCode of your GSM/UMTS network (you're 'located' then in center of that country), or even CellID of the GSM cell (tower) you're in. There's however no such thing like "triangulation" for GSM/UMTS. "Normal" SUPL is via internet, no matter if provided by GSM/UMTS or WLAN or even USB-networking/whatever.

What GSM frequently does is: it provides the same AGPS data (Ephem and Alm) via a hidden data channel in the normal network, see the Radio Resource LCS (Location Service) Protocol as specified first in GSM TS 04.31, or http://security.osmocom.org/trac/wiki/RRLP (interesting read! You'll frown at your phone for what it may do on the [hidden] Control Plane Protocol without telling you)

A sidenote: for systematically obscure reasons the N900 SUPL implementation needs a fairly correct time&date on device to work. Even if SUPL needs some time stamp for delivering the right period of Alm/ephem data (instead of a obvious `NOW´), obviously the devels forgot that - when they already have access to internet to get SUPL data from server - they also can get current time by e.g ntp. Not all carriers provide the (correct version of) timestamp on their network that's used by N900 "automatic time adjustment". Probably exactly when they also don't provide CCP AGPS.

/jOERG

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

ping time is completely irrelevant for AGPS
/j

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

you need nano editor, do you have installed it?

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

unless something odd is going on, like nano having some sort of superpowers, no-one _needs_ nano !

Anyone doing anything on a unix-like OS needs (yes) to know vi.

So would y'all stop being so weird

*end rant*

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

I was using since now supl.nokia.com but positioning needs a lot of time.
Now checking with ping to supl.nokia.com, it seems the nokia server is down.

Will see if positioning now it will be faster

Re: [Tutorial] Faster A-GPS response on Nokia N9
 

Chilango, I have been experiencing the same thing. Of course, that's after I learned that I have to open the Drive app, it sits at the startup screen, swipe it sideways and look at all apps running and watch until it shows a map, then click on it to be the app on the full screen.

I just took a vacation with the family and noticed it took a very long time for maps to come up (and I downloaded the entire country map long ago). I came here to find out what may be wrong and had the same discovery - supl.nokia.com resolves to something else, but gets no ping replies. I left the nokia site as the secondary provider, but now Google is the primary and it comes up quickly.

Thank you (years later) for this find, elieserleao, if you even still check these forums. :)

Now to find out why my N9 is moving slower in all other apps these days than in the past.