Samsung Galaxy S2 Discussions

[yaozer]

I have just rooted my Galaxy S2 yesterday, and I am currently enjoying the freedom! Freezed a lot of bloatware!

Anyway, it seems to me my S2 acquires GPS signals slower than my other devices. From cold start, it would take me probably 5 minutes. If I close Navitel, and after 5 seconds turn it on again, my unit will lock almost instantaneously, 2-3 seconds. BUT, if I only turn it on again after 10minutes, it will again go through the locking phase, and might take around 30seconds to get a lock. The reason I'm complaining is because my wife's Galaxy Tab can do a cold start lock under 20 seconds, and a hot start of 2-3 seconds as long as you turn it on in the vicinity of your last location. If not in the vicinity, it can still lock under 15 seconds. Now it might be because its GPS radio is better than the S2's, OR, its GPS configuration files are better (gps.conf, a_gps, etc).

I have extensive experience with Windows Mobile, owned a total of 4 WinMo devices from 2005 to present. With the Xperia X1i, there is an app called QuickGPS, which is very much functional AND efficient. It connects to HTC servers and download new ephemeris data for you. My Xperia X1i locks the fastest in all my current devices (And really fast too, and yes, faster than my Nuvi 1450). After a fresh download from QuickGPS, cold start is around 7 seconds. Hot start, same vicinity, instantaneous. Hot start, different location, around 3 seconds.

With this fact, I'm thinking maybe I should tweak the GPS configuration files in my S2. I really believe its pointers are not using the right SUPL servers, time servers, etc. I wanted to get LBSTESTMODE (new name is AngryGPS) to work, but it seems it is either blocked or removed from our version of Gingerbread. My wife's Galaxy Tab has this (though I can't launch it, need to research more).

Anyway, I'm currently using the GPS Status And Toolbox app to download ephemeris data whenever I connect to the internet. But my S2 still hunts for GPS signals, not very quick.

Any suggestions on how to edit these pointers (time servers, SUPL, etc)? I believe the Fasterfix app changes time servers, I will also try it out. Monkeyking suggested the GPS Booster app, I will try it out too.

[Monkeyking]

Great! An S2/navitel thread.

Btw, what servers did you choose in faster fix? I just chose the asia server, I see there is an option to use custom settings, anybody know which server Philippines users should choose?

[travelbug]

today i got a signal in 45 seconds from a cold boot.
i reset agps and downloaded new data last night so that may be the reason why.
from threads in xda they do suggest that you have to reset your agps for the new data to be implemented.

also ive read that gps status together with fasterfix will give you the best/fastest gps acquisition. fasterfix looks like an app that automatically downloads region specifi sat info to aid agps and it seems like it uses the same protocols as the darkyrom fix. be aware that you have to be rooted and have busybox installed for it to work.

you guys may want to try it out...

[travelbug]

lol i just read your last paragraph OP haha. thought you guys didnt know bout fasterfix yet

[yaozer]

Upon visiting http://www.pool.ntp.org, I found out that the Philippines has time servers, though it says there there's not enough capacity to handle the traffic. Look at this page:

http://www.pool.ntp.org/zone/ph

I might try using the ph.pool.ntp.org server and see what happens. If it is not better, I'll go back to using the asia servers.

By the way, apparently the gps.conf file can be treated as a text file. Try opening yours (I just tapped it via Root Explorer and it opened correctly). The original gps.conf that came with my S2 points to north.america.pool.ntp.org!! SUPL is correct though, supl.google.com, port 7276.

I tried opening the gps.conf (Asia) file from the Darky's ROM forum, it shows that it is pointing to multiple servers:

asia.pool.ntp.org
0.asia.pool.ntp.org
1.asia.pool.ntp.org
2.asia.pool.ntp.org
3.asia.pool.ntp.org

I think this is better as it can cycle through when another is too busy. As for the xtra1.gpsonextra.net/xtra.bin servers, I don't think this works here in the Philippines (or even Asia). It might only cater to the US and Europe.

Regarding Faster Fix, I haven't tried it, but do you guys think it updates gps.conf? Or is it updating another file? Also, anybody knows what file is being updated with new ephemeris data? I really want to know what app updates what file, and what makes a difference.

[Monkeyking]

If you launch faster fix, your current server is listed there then you get to choose a server, mine is set to asia.pool.ntp.org, so the same as Darky's rom.

I'm also curious how gps status updates the agps data, does it do it automatically in the background? Or do we have to launch it manually to refresh the data?

[yaozer]

Hmm so Fasterfix only gives you one server? It cannot inject more? Also, can you please check if your gps.conf file was updated, its modified date equal to the date you changed the server from Fasterfix. From this, we will know if it directly changes this file, or it changes some other one we have yet to discover.

Regarding the GPS Status app, I believe you need to run it for it to download, and while you are connected to the internet. And based on the interval setting you have set, it will download Ephemeris accordingly. I left it at 1 hour interval, so that when I run the app, it will almost always fetch data.

[travelbug]

the problem with gps status and agps is that it will only update your agps when the program is on and it has no background running services. so even if it is set to 1 hour, it will not update unless you manually launch the program.

there is also a switch that it will d/l data only with a wifi connection and i think this is on by default. but again the app has to be running for it to do this.

almost all threads ive seen on gps status also recommend resetting data before downloading new xtra values.

[Monkeyking]

What directory does the gps.conf file reside in? I can't seem to find it using root explorer.

[travelbug]

system/etc

[travelbug]

Upon visiting http://www.pool.ntp.org, I found out that the Philippines has time servers, though it says there there's not enough capacity to handle the traffic. Look at this page:

http://www.pool.ntp.org/zone/ph

I might try using the ph.pool.ntp.org server and see what happens. If it is not better, I'll go back to using the asia servers.

By the way, apparently the gps.conf file can be treated as a text file. Try opening yours (I just tapped it via Root Explorer and it opened correctly). The original gps.conf that came with my S2 points to north.america.pool.ntp.org!! SUPL is correct though, supl.google.com, port 7276.

I tried opening the gps.conf (Asia) file from the Darky's ROM forum, it shows that it is pointing to multiple servers:

asia.pool.ntp.org
0.asia.pool.ntp.org
1.asia.pool.ntp.org
2.asia.pool.ntp.org
3.asia.pool.ntp.org

I think this is better as it can cycle through when another is too busy. As for the xtra1.gpsonextra.net/xtra.bin servers, I don't think this works here in the Philippines (or even Asia). It might only cater to the US and Europe.

Regarding Faster Fix, I haven't tried it, but do you guys think it updates gps.conf? Or is it updating another file? Also, anybody knows what file is being updated with new ephemeris data? I really want to know what app updates what file, and what makes a difference.

arent these pool servers for syncing time?
how can they help get a better gps fix?

[yaozer]

From what I understand, the time servers need to be as accurate as possible for our location. The time it provides is needed to somewhat "predict" where the satellites currently are, it is part of the equation. From what I've read, GPS satellites travel at a speed of 14,000 km/hr, so I think an offset in milliseconds can make a difference in lock speed. The idea is to get the right time synchronization data at the least amount of time. If the server is farther than our location, there might be some delay in getting it, therefore adding to the offset. I may be a bit off, maybe someone with better knowledge can shed some light. In short, I just know that the time server data is needed in the equation to get a precise lock, synchronization is key.

[travelbug]

From what I understand, the time servers need to be as accurate as possible for our location. The time it provides is needed to somewhat "predict" where the satellites currently are, it is part of the equation. From what I've read, GPS satellites travel at a speed of 14,000 km/hr, so I think an offset in milliseconds can make a difference in lock speed. The idea is to get the right time synchronization data at the least amount of time. If the server is farther than our location, there might be some delay in getting it, therefore adding to the offset. I may be a bit off, maybe someone with better knowledge can shed some light. In short, I just know that the time server data is needed in the equation to get a precise lock, synchronization is key.

sounds like a good explanation to me.

fasterfix does seem to do the same thing as the darkyrom fix but in app form instead of a root edit.
when i tried the darkyrom fix i did get a fix much faster but the fix was really poor as it only locked on to 4 satellites.
tell me how it goes for you though

[yaozer]

I will try the ph.pool.ntp.org time server sometime soon. I hope it is not as busy as the NTP site says it is.

By the way, I've just looked in my wife's Galaxy Tab, its gps.conf is pointing to north-america.pool.ntp.org!!! Now I'm wondering how and why it locks really fast. There is definitely something else at play here. Either that, or the S2's GPS radio is inferior to it.

[Monkeyking]

What the? My gps.conf has a modified date of 1-16-70!