If I remember correctly
jaliy, you are on the
GT-i9100 with the
XEU,
UK, firmware. Quite a few Canadians have requested a different modem on the, "All Things Root", forum in an effort to improve their signal and it seems that the
XXKG6 and
UGLD3 modems work well in Canada.
However, I know that you are un-rooted and therefore constrained to the modem that comes with the
UK firmware.
Therefore, I can only suggest doing a manual signal/network provider search and re-registering your phone with your network to see if this improves your signal...
1.
Settings >
Wireless and network >
More >
Mobile networks >
Network operators.
2. Let the screen populate with all the available carriers.
3. Select a carrier that is not your own. You will be told, after trying to connect, not allowed or No way Jose.
4. Repeat this with one or two other non carriers.
5. Finally, select your own carrier, Automatic, and reconnect your phone again.
This procedure should ensure that your phone locks on to the strongest signal for your carrier.
I normally give a modem 1 or 2 days to, "bed", in before deciding if it is any good or not.
To check your signal strength, go to...
Settings >
About phone >
Status >
Signal strength
Here you will see 2 results..
-dBm. The lower the -dBm, the better. For instance, -65dBm is better than -83dBm.
asu. asu, or, "Arbitrary Strength Unit", is also important to signal strength and, unlike -dBm, the higher the value, the better.
At home at the moment, indoors, my signal strength is showing as -83dBm and 16asu.
For more information on network signal strengths and how they are calculated, see,
here.