iPhone 5 will not stay connected to LTE while on a voice call.

iPhone 5 will not stay connected to LTE while on a voice call.

I noticed that something has either changed in the network and/or the Iphone 5.  I currently have a 64GB Black iPhone 5 and the grandfathered unlimited plan.  I noticed while on a voice call, the internet becomes utterly useless.  I could not find a direction that was 10 miles away from me because the map would not generate.  Just sat there loading.  I could not do an internet search for anything without it taking more than 35 seconds, connecting to the app store took close to a minute, and checking mail was useless.   These issues were not occurring on my first iPhone 5 (this is my 3rd).  I even bragged at how fast I could do a search for directions, load them in apple maps, all while on the phone talking to someone.  For some reason, this no longer works.

 

I tested this theory on my own phone and a few of my coworkers phones.   It is reproducible.  The speeds experienced when the phone drops off of LTE is slower than 3G/4G speeds that you would normally experience when turning LTE off.  This was also tested. 
I reset, restored, set my phone up as new.  Reset network connections, etc several times and this still happens.  I called into AT&T and was told that this was normal and I should not expect a phone to use LTE while making voice calls.  Why not?  The phone isn't using LTE to make voice calls, its using the 3G network to make voice calls.  That's the purpose of the phone having 2 antennas, to be able to do this.   To tell me that this is not an option, when I witnessed it on my first iPhone is unacceptable. 

 

The results are below.  They should be read from BOTTOM TO TOP. 

 

What you will see is my LTE test that was ran before the call, 1 test with LTE turned off, 2 calls while on the phone with AT&T, and 2 calls after I got off the phone.  Took 3 more resets to get it back to normal speeds.  The 54.61 mbps is a rare occurrence.  I normally average 20 -30 mbps down and 20 mbps upload. 

 

As you can see, while I'm on the phone I get 0.00 mbps upload speed.  To tell me this is normal can not be accepted as a viable answer.  These tests were done slightly north of downtown Atlanta, GA in between AT&T cell phone towers.  Signal was not an issue. So I went from 6.70 Mbps to 0.60 mbps while on the phone.  At least give me normal 3G/4G speeds while on the phone.  I was also told that although my strength was low, this was still within normal range.  You can't tell me that 0.60 mbps and 0.00 mbps upload speed are the normal speeds.  I did not experience anything as slow as this while on an iPhone 4.  Sorry I couldn't compress the screen shot any more because I did these tests several times. 

 

My average speeds are below. 

 

 

These problems seem to happen only only on LTE and when you attempt to make a phone call.  On wifi the upload speed will suffer, but the download speed will still be around 20 mbps, but that's probably because of the ISP.   These results tell me that this is an option that can be turned on or offand some of the new iPhone 5's did not experience this.  My first iPhone 5 before I took it back was a beast with multitasking. This was a bragging point that I could do all this while actually on the phone getting the information/ directions I needed. It has to be a recent update in the network settings somewhere that is causing this issue.If you could please test your handsets and confirm whether or not this is happening on your iPhones?  A bug report has been submitted to Apple and the concern has been voiced with AT&T (who sent me back to Apple). 

Message 1 of 24 (38,496 Views)
Professor

Re: iPhone 5 will not stay connected to LTE while on a voice call.

You've got how it works wrong. When on a call, data reverts to 3G/4G. It doesn't stay on LTE. Regardless of the numbers of antennas, Apple choose to put the radios on a single chip for space and power considerations. Because of that design choice, the iPhone 5 can't run the LTE radio for data at the same time it runs the GSM radio for voice. When on a call, the phone falls back to 3G/4G, which can handle simultaneous voice and data.

At least that's how it's supposed to work. Some people have reported problems with the phone falling back when a call comes in.
Message 2 of 24 (38,467 Views)
Master

Re: iPhone 5 will not stay connected to LTE while on a voice call.

At least AT&T can do data and voice at the same time something Verizon and Sprint can't.

Message 3 of 24 (38,458 Views)

Re: iPhone 5 will not stay connected to LTE while on a voice call.

But that's just the problem.  When it switches over, the speeds are slower than going over to 4G speeds normally and this doesn't explain my first iphone 5 being able to stay connected to LTE while on a voice call.  I've made VOIP calls and it doesn't drop me off of wifi when ti connects to 3g/3G, so I believe the capability is there.  The iphone 5 has two LTE antenna's along with two cellular antennas.  It might be controlled by one quadcomm chip, but I believe I should at least get "normal" 3G/4G speeds when talking on the phone, not have an usuable device everytime I get a phone call.

Message 4 of 24 (38,393 Views)
Master

Re: iPhone 5 will not stay connected to LTE while on a voice call.


mythicalcaesar wrote:

But that's just the problem.  When it switches over, the speeds are slower than going over to 4G speeds normally and this doesn't explain my first iphone 5 being able to stay connected to LTE while on a voice call.  I've made VOIP calls and it doesn't drop me off of wifi when ti connects to 3g/3G, so I believe the capability is there.  The iphone 5 has two LTE antenna's along with two cellular antennas.  It might be controlled by one quadcomm chip, but I believe I should at least get "normal" 3G/4G speeds when talking on the phone, not have an usuable device everytime I get a phone call.


From all that I have read you must have been on HSPDA+ for both data and voice which they do call it 4G but not LTE as far as I know that is not currently possible and if so Verizon and Sprint would have voice and data at the same time.

Message 5 of 24 (38,332 Views)

Re: iPhone 5 will not stay connected to LTE while on a voice call.

I have an AT&T 64GB IPhone 5. Sorry if I didn't put that in the post somewhere.
Message 6 of 24 (38,259 Views)

Re: iPhone 5 will not stay connected to LTE while on a voice call.

 

AT&T's statement on using both voice and data at the same time. 

 

https://docs.google.com/viewer?a=v&q=cache:7KQ7FNVDZf4J:www.att.com/Common/about_us/files/pdf/talk_s...

 

Message 7 of 24 (38,251 Views)
Master

Re: iPhone 5 will not stay connected to LTE while on a voice call.


dwill05 wrote:
You've got how it works wrong. When on a call, data reverts to 3G/4G. It doesn't stay on LTE. Regardless of the numbers of antennas, Apple choose to put the radios on a single chip for space and power considerations. Because of that design choice, the iPhone 5 can't run the LTE radio for data at the same time it runs the GSM radio for voice. When on a call, the phone falls back to 3G/4G, which can handle simultaneous voice and data.

At least that's how it's supposed to work. Some people have reported problems with the phone falling back when a call comes in.

Every thing that I have read supports that the iPhone reverts to 4G/3G data when on a voice call. 

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Message 8 of 24 (38,219 Views)
Master

Re: iPhone 5 will not stay connected to LTE while on a voice call.


mythicalcaesar wrote:

 

AT&T's statement on using both voice and data at the same time. 

 

Google Quoted Document

 


That documents just states voice and data at the same time on a GSM network which is true.

If you read Apples "Understanding Cellular Data Networks" it shows the iPhone does not support both voice and data over LTE at the same time.  The footnote states it will switch back to 3G for data during a voice call.  

http://support.apple.com/kb/HT1976

 

LTE networks

LTE is available with supported LTE carriers.

LTE LTE No1 iPhone 5 and iPad (3rd generation) Wi-Fi + Cellular only.2
  1. iPhone 5 (GSM model) will switch to 3G for data during voice calls.
  2. Requires a supported LTE carrier. For iPhone, see this article. For iPad, see this article.
Message 9 of 24 (38,196 Views)

Re: iPhone 5 will not stay connected to LTE while on a voice call.

If you read my original message, you would have seen that I said that 3G/4G is unusable. And what is being requested is not truly simultaneous voice and data.  Voice will be on 3g/4G understood, but maps, app store, email, etc should still be on LTE.  The link still bypasses this. and AT&T and Apple have no explanation and are unwilling to give one.  The simple tasks that I can still do on my iPhone 4 can not be done on the iPhone 5.  I would do a little more research to see that I am not the only one experiencing the issue before going into attack mode. 

 

If I need to repeat it to you.  This DID work on my white iPhone 5 when I first got it - NO MATTER  what is shown on the website.  I would rather have a post coming from someone experiencing the same issue or someone from Apple or AT&T not a proxy.   The phone is capable of this and there is still no explanation of getting less than edge speeds on data when talking on the phone. 

Message 10 of 24 (38,011 Views)
Professor

Re: iPhone 5 will not stay connected to LTE while on a voice call.


mythicalcaesar wrote:

If you read my original message, you would have seen that I said that 3G/4G is unusable. And what is being requested is not truly simultaneous voice and data.  Voice will be on 3g/4G understood, but maps, app store, email, etc should still be on LTE.  The link still bypasses this. and AT&T and Apple have no explanation and are unwilling to give one.  The simple tasks that I can still do on my iPhone 4 can not be done on the iPhone 5.  I would do a little more research to see that I am not the only one experiencing the issue before going into attack mode. 

 

If I need to repeat it to you.  This DID work on my white iPhone 5 when I first got it - NO MATTER  what is shown on the website.  I would rather have a post coming from someone experiencing the same issue or someone from Apple or AT&T not a proxy.   The phone is capable of this and there is still no explanation of getting less than edge speeds on data when talking on the phone. 


If you look at the apple support link in the post above, even Apple, who made the phone, states that the AT&T GSM iPhone 5  reverts to 3G for data when on a phone call.  If the phone was capable of LTE data while on a voice call, as you claim, why would Apple state otherwise?  They surely know the capabilities of the phone.

 

the phone still should have 3/4G data while on a call.  If that isn't happening, then something is wrong.  However, you are NOT going to stay on LTE while on a call.  The phone simply doesn't work that way.

Message 11 of 24 (38,000 Views)
Highlighted
Contributor

Re: iPhone 5 will not stay connected to LTE while on a voice call.

I'm having the exact same issue.  Did you ever get anything resolved?

Message 12 of 24 (35,588 Views)
Professor

Re: iPhone 5 will not stay connected to LTE while on a voice call.

There is nothing to be resolved. The AT&T phone will not stay on LTE while on a voice call. While on voice, it will drop to 3/4G for data. That's the way the phone is designed to work.
Message 13 of 24 (35,570 Views)
Contributor

Re: iPhone 5 will not stay connected to LTE while on a voice call.

[ Edited ]

Kind of the same problem here.  This is what I have found with my 32 g iphone 5.

 

Start with 3 bars of LTE.

As soon as a dial or receive a call it reverts to 4 bars of 4g.

After being on the phone for 4-5 minutes it reverts to 4 bars of EDGE. (this has been tested mutiple times.  Also while on the phone with ATT Tech support) (NO MOVING AROUND SITING IN THE SAME SPOT AS WHEN THE CALL WAS MADE)

As soon as the phone call is ended. The phone returns to 4g within  30 seconds or so. 

Then within a minute the phone returns back to LTE.

 

Any ideas on this?

 

Message 14 of 24 (34,397 Views)
Scholar

Re: iPhone 5 will not stay connected to LTE while on a voice call.

IMHO the title/subject of this thread needs to be changed or else this thread should be closed since it is a given fact that, for better or for worse, an iPhone 5 will drop from LTE to 4G/3G (and apparently, even to EDGE) when on a voice call while connected to AT&T's cellular network.  That it (currently) does that is not some sort of bug or defect; the issue about getting slow 4G/3G data speeds while on a voice call may be a valid concern but again, it has nothing to do with the iPhone 5 not staying connected to LTE while on a voice call (on AT&T's network).

Message 15 of 24 (34,338 Views)
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