I have performed many APN, ROM, and baseband experiments and have successfully routed out every variable contributing to signal loss on data, voice, drop call, and signal blackout. I can produce a full detailed on this if anyone wants. Will just take me some time to collect all my data.
To the limits of not be a Dev nor a coder I believe the issue is with how the phone handles frequency changes based on signal strength or data. There must be a code or script that tells the phone to switch to a lower band if the primary band is below a certain strength. If there is it can be changed to allow the band to be switched more effectively automatically if any of the Lowe bands exceed the primary bands signal strength beyond a certain tolerance. Thus insuring a constant signal strenght between all 3 bands that can be used automatically. The function is allready there and in use but it needs to be found and hacked.
This is where the Devs we rely on come in. The above is all theory and is the limit of my knowlage of how it works. Its the Devs that can take this idea and realise it. I am fairly sure this is the direct cause for the majority of our in call problems. I would be more than happy to vigorously test this and offer full reports if given the chance. If I'm wrong and I'm barking up the wrong tree here let me know please. I want to help but I really don't want to lead anyone the wrong way.
Thanks
[BUMP]
Developers (you know who you are) . Trying my best to help on this but it needs to be confirmed at minimum. Really need someone with more knowlage on this.
Thanks in advance oh wise and powerful developers. Consider your posteriors kissed. Lol
Thanks for taking the initiative on this. I have a couple questions:
How did you collect your data? (Not looking for a detailed answer, just a quick rundown)
Did you use a control?
So, im a little confused on what your looking for exactly. Are you asking if there is a way to hot switch the base bands on the fly automatically when signal strength is low?
I am interested to see what you have, but want to fully understand what your looking for.
Colbur
The majority of my data is notes. As a control I used the stock baseband, stock rom. Completely cleaned the phone of any app and used it solely for phone called during the day. I noted the signal strength changes when traveling in and out of various coverage zones. 2g 3g 4g . Made note of how long it took to change then moved again. Seemed very erratic in how the phone decides what signal to use. Couldn't seem to understand why in some cases it would stay on a 4g band when a 3g was twice as strong in the dame spot.
So after changing roms and apn's I cunducted the same experiment with the same average results. Used the same rout and time in stops.
Changed baseband same rom. Same experiment. Got the same average.
Changed baseband and rom again. Again same results.
I think the problem is how the phone decides what band is best at any given time. If its set to pic a band with a higher data rate then it would stick on 4g even though a 3g signal is much stronger. How often it changes is also an issue. Polling to often will drain the battery and depending on how the variables are set it will swing rapidly across bands while in use. It would be great to crack open the files that decides this so we can tweek it to fit our geographic location better.
An update
This specific behavior is in direct relation to the Baseband. While the APN is dealing with credentials the baseband in our case determines the hand shake and frequency from quadrant to quadrant when rolling past towers .
The other eminent and probably the most important is the refresh rate of the network. The more frequent its set to refresh the more it uses battery . If its set to low then you loose signal more often.
Cab121 said:
An update
This specific behavior is in direct relation to the Baseband. While the APN is dealing with credentials the baseband in our case determines the hand shake and frequency from quadrant to quadrant when rolling past towers .
The other eminent and probably the most important is the refresh rate of the network. The more frequent its set to refresh the more it uses battery . If its set to low then you loose signal more often.
Click to expand...
Click to collapse
I'm assuming that this is going to be for a particular region as where I am, I never have experienced the issues with the phone as others have.
Detailing your region and the exact method you used to test this would be a good idea as well, that way others in different regions can test it out and see if they get the same results.
From what I notice on my phone (CM7.2+, v21E), when the signal strength goes below -110dB on 3G, it switches to 2G. My phone is the P920 so there's no 4G. I think using empirical data with hard numbers is better than using the number of bars as a gauge, since according to the P920 service manual:
In 3G
4 bars: over -88dBm +-2dBm
3-4 bars: -88dBm +-2dBm
2-3 bars: -96dBm +-2dBm
1-2 bars: -104dBm +-2dBm
0-1 bar: 110dBm +-2dBm (at this point it switches to 2G mode automatically)
In 2G
4 bars: over -91dBm +-2dBm
3-4 bars: -91dBm +-2dBm
2-3 bars: -99dBm +-2dBm
1-2 bars: -103dBm +-2dBm
0-1 bar: -105dBm +-2dBm
As seen from the above, there's a pretty large range between each bar of signal so numbers are better I think. Furthermore when you factor in the fact that dBm is calculated in logarithmic form, an increase of -10dBm (-80dBm --> -90dBm) would mean a 10000 fold decrease in performance.
This is fantastic data and a great post. What are you using to log your signal data?
Been using a few maps but I'm uncertain of there accuracy .
The LG stock rom only allows you to use the bars as a gauge of your signal strength. I'm using CM atm, it allows you to display your signal strength in dBm instead which is very helpful for things like this.
Related
So we just got 3G here this week, but when I am on the 3g network, my cell triangulation doesn't work. can someone with 3G in their city confirm that it is working for them so I can stop worrying about it?
Thx
NC?
How does one know if triangulation is working exactly, ha
SLC utah
make sure your GPS is off then open Google Maps and hit menu - My Location.
I go to lunch in a few and will test. Raleigh NC just turned 3G this week as well.
Confirmed: same issue... can not find my location, where edge can (did not cut off 3g, basing that off of 1 year of using maps up till this week when i got 3g in my city).
Anyone have thoughts on this?
For that matter.... why do i not have 3g in buildings/homes? I only have 3g when outside.
Worked on edge.
In phone status it shows my network as UTMS, not 3G (used to say Edge).
I guess this in normal?
Think about how "triangulation" works (improper name, really):
Along one of the low-bandwidth data channels (along with network time, network name, etc.) are a few small numbers: your MCC and MNC (describe which network: 310/410 for att usa, 310/260 for tmo usa. Those are compared against the return from AT+COPS (or actually a little database if you see "T-Mobile" or "AT&T", compared with "Voicestream Wire", "Cingular", "ATT0", or often just "") to get your network.
Those are then combined with two more numbers, the LAC and CID. The Location Area Code is unique to a region on a network (pretty wide range), and the CID is unique per tower. There is no lookup (similar to COPS) that provides a location from a given cid. This means that you have to look up the LAC/CID against a database (MCC/MNC sometimes speed up searching/possibly sort out duplicates - idk). There are a few of these databases available - there's one free one which I'm thinking about, google probably keeps one (they keep a wifi database too), microsoft probably keeps one, etc. AFAIK, there's no unified database... please correct me if I'm wrong. However, the networks do provide their tower lists to big-name lists.
One last thing to think about - the companies will always try to sell you on the idea that they use multiple towers and find the area their coverage overlaps, or that they use "the unique footprint of a tower"... basically, they put your rough location as the complete coverage area of the tower to which you are currently registered. Actually, they don't really calculate it well - it's just a circle around the tower. What google means by this second claim (the footprints one) is that some of the circles are different sizes, depending on whether the cell is full power, low power, etc. This is especially provable in my bedroom - I have access at full signal to two 3g towers (I love this area ), that seem to overlap right here. This means that, when I use google maps, or another similar program, the circles constantly move between the two. It also means that I get spammed with unsolicited +CREG's on my modem line, as it moves around .
Combining all this knowledge, I know exactly what's wrong. #1: the lac/cid on the EDGE tower elements is different than the 3g towers (makes sense, for signal range calculations), #2: google knows about the LAC/CID on the EDGE towers, and #3: google doesn't yet have the new 3g towers' LAC/CID information in their database. Therefore, the program is passed information it doesn't know about, so it simply returns an error.
Proposed solution: wait a week or two
ADDITION: You don't have 3g in houses because the 3g signal does not penetrate as well (It's on a higher frequency, and the signal drops after less interference than edge). Since these are new towers, they may also be running at reduced power.
I'm in SLC as well, and can also confirm wierdness with the non-GPS location over the first couple of weeks... including one day where my phone absolutely insisted that I was just outside of San Diego. Quite mean of my phone to tease me like that considering that I was in West Valley City at the time. It seems to be getting better as time goes on.
^^ wow, I can feel the authority. Thanks for a great post. I think you are correct, the 3G seems to be getting better coverage (sometimes getting it in my house now). I trust t-mo and google, thank you man.
I don't know EDGE technology (never delved into it), but I seriously doubt poly's claim that it uses a different frequency than 3G. If you're using a USA spec G1, then your tphone has a single radio for t-mobile's 1900 MHz band.
The issues you are noticing with 3G coverage are more likely due to SIR parameter set by the deployment engineers (i.e. they are telling the 3G cell to only 'talk' to your phone if the signal is strong).
This is just a guess, though. There could be any number of issues going on, like some misconfigured settings on the RNC's for your sector (which makes sense if the coverage is new).
UMTS is the 3G technology that T-mobile (and AT&T) use, so that is normal.
Tarzanman said:
I don't know EDGE technology (never delved into it), but I seriously doubt poly's claim that it uses a different frequency than 3G. If you're using a USA spec G1, then your tphone has a single radio for t-mobile's 1900 MHz band.
Click to expand...
Click to collapse
yeah, it's generally not too much of an issue - all the frequncies are pretty close (I think the 850mhz stuff from att might go a bit better than the old 1900, but it is pretty close). And, as I just discovered, tmo is entirely 1900mhz, so that part was mistaken. The rest should be accurate to the best of my knowledge (eg. EDGE can take more interference before it drops, etc.)
EDIT: Nope, their entire EDGE network is 1900mhz, but their 3g is only 1700/2100. So, it's a tossup, and that close makes not much of a difference.
My carrier had some little problems during the past weeks, aparently they were working on something. I sometimes, for short periods, did not have data connection or no servic at all. Now the problems are gone and a speedtest today showed that at my home, the download speed went from an average 1 Mbit to over 5 Mbit!
However, the H symbol won't go away anymore! It used to switch to 3g when not data was transferred. I assume that this will influence battery life.
Is there anything I should be worried?
From what I recall, H is faster than 3g, as long as your in a good signal area, the H will always be visable, it will only drop down to 3g if the area your in has no H signal... and if there is no 3g it will drop to a 2g signal... simples, having the H does not meen that data is being transfered!
I am aware of the different speed levels, what I experience now is that the H symbol stays all the time, whereas it used to change to 3g when idling even in areas with very good reception...
GMH24 said:
I am aware of the different speed levels, what I experience now is that the H symbol stays all the time, whereas it used to change to 3g when idling even in areas with very good reception...
Click to expand...
Click to collapse
Wait, I don't get what you're saying. Let me clear it up:
Very good reception = H
Not so good reception = 3G
You want to see H (means HSDPA which is a a type of 3G data, but it's faster).
MrSimtang said:
Let me clear it up
Click to expand...
Click to collapse
Okay, I'll try that too!
I live in an area with very good reception and therefore the phone used to switch from 3g to H whenever data was transfered and back . Now, however, it stays on H all the time and does not switch back to 3g when no traffic occurs.
It is just a change in the pattern my phone behaves so I wanted to get some info on that...
Hi, it's your phone doing what it should by seeking the best signal.
H refers to HSDPA which is based on UMTS (3G). Consider it a 'turbo' version of 3G. It's sometimes also referred to as 3G+ because it's faster then 3G but not really 4G technology. The tower in your area most likely got upgraded to HSDPA that's why you don't see the 3G icon anymore.
Sent from my GT-I9000M using XDA App
Not correct, he mentioned that his phone was using H on demand before, so the capability was there already.
The problem is that H mode uses more battery than 3G, which is why it normally only switches to H during data transfers instead of continously being on.
Possibly your provider made a change which forces your phone to stay in H mode. On hardcores homepage (see speedmod kernel thread) he describes a method to manually deactivate H mode if you want to play with it.
Hope that helps.
Sent from my GT-I9000 using Tapatalk
seems to be the explanation... Suddenly I have ~6 Mbit, so almost unsurprisingly there had to be a catch
as for disabling H, it would be permanently so not quite an option. I guess, I'll have to live with it but nevertheless I'll call customer support..
Hspa and 3g are actually different technologies, but can be used on the same site and freq. If you have noticed that your phone is nowdays all the time showing H ( hspa ) and not in 3g like before it means that your carrier has expanded their hspa features and capacity of the network on that area. Main difference between these two tech is of course the speed and how network resources are shared between the users. In 3g you have dedicated ones, but speed limited and in hspa you are sharing the resources between other ones under that cell area. hspa is good if you are near by the cell and there is not too many users from battery consumption point of aswell from througput point of view, 3g is better if you are on the cell edge due to dedicated resources reserved only for you. Main point is, battery consumption of your phone depends mainly how you use your phone ,what kind of applications you have and how often those are connecting/contacted by the network.
Browsing in 3g sucks!
Sent from my GT-I9000 using XDA Premium App
I live in a weak signal area, my power meter (found at: setting,wireless, mobile network settings, networks type and strength) rarely if ever goes below -90 dbm. I often monitor the VZ network by using it. I use my phone for Internet (even with a weak signal my phone has provided me better service than my other options).
I have often observed an odd behavior reported by the power meter, the meter will jump from its current reading to -1 dbm. This occurs only on the 3G network tower. There is also a 1X tower at 4 miles away that I have not observed this very unlikely power reading.
Anybody else have this experience?
Could there be a front end amplifier/attenuator on the radio? If so I would think my phone has a defect.
Thanks
Steve
Update: I took the lack of folks having the same problem and another issue this phone's hotspot/tether process to mean this phone had a defect. I was able to replaced it today with a new phone.
I observed that the new phone has the same issue.
Does anyone have schematic for the front end of these radios?
(I wouldn't think this to be possible that LG would give out this information, but I thought I would as)
My understanding is that the radios have not been released, giving us so much trouble getting ICS and other things to work. as far as signal issues... i think it's the phone it self. not yours, but all of ours. I know in a small town out where i live, i have to use a different carriers tower, Verizon doesn't reach well... and my friend still has 4G. he's using thunderbolt, other friend has 3g through at&t... so i think our radios may be underpowered.
i recently unlocked, rooted and s-off my htc one, on stock i used to get around 5/4 signal bars and now i only get two/three.
im currently running trickdroid 7.5 rom 4.2.2.
so im looking for a radio which would work for orange/EE in the UK.
please can someone help, or point me into the right direction
this is the one for the 4.2.2 firmware
http://forum.xda-developers.com/showpost.php?p=42139108&postcount=18404
Are you sure that it is not the same level? Don't be fooled by the bar looking different, remember that it might show 2 bars of LTE but that could still be better than 5 bars of H+ (as an example).
So if you used to get 5 bars of 3G but your now getting 2 bars of H or H+ then you are better off even though its less bars.
Please do not take this as me treating you as if you are stupid, I am not, I have come across a lot of people recently who thought the same, and it turned out to just be a different type of signal.
fixed
okk i just flashed 1.29.401.12 Radio and it's back to normal.
i found it here http://forum.xda-developers.com/showthread.php?t=2245615
Lennyuk said:
Are you sure that it is not the same level? Don't be fooled by the bar looking different, remember that it might show 2 bars of LTE but that could still be better than 5 bars of H+ (as an example).
So if you used to get 5 bars of 3G but your now getting 2 bars of H or H+ then you are better off even though its less bars.
Please do not take this as me treating you as if you are stupid, I am not, I have come across a lot of people recently who thought the same, and it turned out to just be a different type of signal.
Click to expand...
Click to collapse
thanks for the input but!
i never said i was using my data connection,
Same principle applies even with data off.
Sent from my HTC One using Tapatalk 4 Beta
Lennyuk said:
Are you sure that it is not the same level? Don't be fooled by the bar looking different, remember that it might show 2 bars of LTE but that could still be better than 5 bars of H+ (as an example).
So if you used to get 5 bars of 3G but your now getting 2 bars of H or H+ then you are better off even though its less bars.
Please do not take this as me treating you as if you are stupid, I am not, I have come across a lot of people recently who thought the same, and it turned out to just be a different type of signal.
Click to expand...
Click to collapse
So if I have 5 bars when set to "GSM" only but 2-3 when set to "GSM/CDMA" .. that's as good?
I'm being serious btw, I normally set mine to just GSM as I seemed to have more signal but if there isn't any point then I won't bother lol ..I'm in the UK btw and on a network that doesn't support LTE (I think)
AllAboutTheCore said:
So if I have 5 bars when set to "GSM" only but 2-3 when set to "GSM/CDMA" .. that's as good?
I'm being serious btw, I normally set mine to just GSM as I seemed to have more signal but if there isn't any point then I won't bother lol ..I'm in the UK btw and on a network that doesn't support LTE (I think)
Click to expand...
Click to collapse
You can confirm the 'type' of signal you are getting at any time in the menu > settings > about part of the phone.
Your phone will automatically switch to whatever the best signal is available at any time, you don't really need to change your GSM/WCDMA settings, unless you really want to force it away from 3G connections (again this does not mean you have to have data turned on).
Cool, I'm not too fussed about what data type it uses as I rarely have data turned on, I just naturally assumed that by switching it from GSM'CDMA Auto to just GSM, meant that I'd have better reception, being that the signal bars went from 2/5 to 5/5 ... You learn something new everyday lol
EDIT: I checked my signal, and I mean my reception, not the data connection type, when switched between GSM/WCDMA Auto and GSM Only and there is a huge difference. I found this guide:
dB Signal - A basic guide
-50 to -60 (very strong, near a cell tower)
-60 to -70 (extremely good, rare)
-80 to -85 (normal downtown)
-90 to -95 (getting on the weak side)
-95 to -98 (weak, dropping calls)
-98 to -100 (bad, hard to stay connected)
-100+ (basically no usable signal)
When I set my phone to GSM Only I hover around -70, which is good, when I switch to GSM/WCDMA Auto it is a different story. I know it changes and finds the best signal, which I might add drains more battery on an already power hungry beast, but I was hovering at -100 which is terrible and often calls were dropping or people were saying it was engaged when infact I hadn't used it.
It's clear to me that in my case, GSM Only is the far better option if I actually want to use my phone to make calls ... Data speeds I'm not arsed about so EDGE is just fine with me.
I've seen some people post regarding less/lower signal bars when updating to the new radios which come with 4.3 and you have LTE.
At first I said "WTF" but then I realized... the bars are now sort-of working as intended...
Let me explain,
If you're connected to LTE, the bars are now based off your LTE signal strength. I noticed even at roughly -110 to -100 I only get one bar. I believe the bars start going up dramatically once you have a signal strength greater than -100 (for example, -95db, -85db) And we all know -130db is the cutoff before we lose LTE.
I figured this out once I turned the phone to "CDMA only" to test. Once on "CDMA only" I had almost full bars, (-70-75db for 3G/1x)
To conclude, if you're on LTE and only have 1 bar, you most likely/probably have great cell phone coverage as that 1 bar is determining signal strength for only LTE. When connected to LTE, you're also still connected to 1xRTT which is used for voice. LTE is only used for Data at the moment.
If you really want to test your cell phone coverage, you can get one of those programs to tell you both your 1x signal and 4G signal simultaneously.
Edit: I forgot to mention, Considering the LTE radio and 1x/3g radio are seperate, you're going to get mixed results depending on signal penetration through walls, trees, etc. From what I've seen so far, as of right now 1x/3g penetrates a bit better than LTE. But, really depends on your surroundings
Thanks for the info. Someone else tipped me off about this, and a few SpeedTest checks confirmed it. In fact, 1 bar with the 4.3 ROM produced slightly better results than the 4.1 ROM with 5 bars.
ED2O9 said:
Thanks for the info. Someone else tipped me off about this, and a few SpeedTest checks confirmed it. In fact, 1 bar with the 4.3 ROM produced slightly better results than the 4.1 ROM with 5 bars.
Click to expand...
Click to collapse
Yup, which makes sense because when connected to LTE on 4.1 the 5 bars are based off your voice coverage, not LTE strength.
Still seems kind of dumb. I'd rather know what signal I have to make a phone call rather than what kind of data I can expect.
Thanks for info !
Sometimes just 1 bar but internet working well, but 4-5 bars it is not working/slower !