ATT disables LTE during voice calls, drops speeds down to 3G

[BoxerGT2.5]

But it could vary per device also.
How many LTE phones does AT&T have available now and do they all behave the same?

Have the SIII and yes, LTE drops when I'm on a voice call and I'm on 4G speeds.

 

[aquadisiac]

Verizon definitely allows simultaneous voice and LTE. I just loaded MacRumors on LTE on my Droid 4 while in a call:

Image

You're right that if there's any limitation, it's with the iPhone, not with the Verizon network itself.

as previously stated not on the iPhone.

 

[chiefpavvy]

Verizon 4G devices get around the voice/data by using multiple radios. One connects to LTE for data, the other to 1X CDMA for voice calls. (Voice is always done over 1X, not 3G or LTE). iPhone 5 does not utilize multiple radios like this so simultaneous voice/data on Verizon is a no go.

AT&T drops LTE down to HSPA+ during a phone call but simultaneous voice/data absolutely does work.

VoLTE will be a reality some day, but it's quite a ways out from wide-scale commercial deployment. Verizon will likely be first with VoLTE just as they were with LTE but we're talking some time yet.

 

[b24pgg]

as previously stated not on the iPhone.

...which I acknowledged when I said "You're right that if there's any limitation, it's with the iPhone."

I just wanted to clarify for others reading this thread that the limitation is with the iPhone device, not with the Verizon network.

 

[AustinIllini]

Verizon definitely allows simultaneous voice and LTE. I just loaded MacRumors on LTE on my Droid 4 while in a call:

Image

You're right that if there's any limitation, it's with the iPhone, not with the Verizon network itself.

Documented on this site: https://forums.macrumors.com/threads/1440402/

Huh? Then why is there a "4G" icon on my screenshot...

It's always been there.

 

[b24pgg]

It's always been there.

Huh? The 4G icon in my status bar definitely disappears or switches to 3G when I don't have 4G coverage.

I don't know quite how else to prove it to you, but that screenshot definitively proves that I can get simultaneous voice + LTE on my Verizon Motorola Droid 4.

 

[AustinIllini]

Huh? The 4G icon in my status bar definitely disappears or switches to 3G when I don't have 4G coverage.

I don't know quite how else to prove it to you, but that screenshot definitively proves that I can get simultaneous voice + LTE on my Verizon Motorola Droid 4.

I agree with you. The iPhone doesn't do simultaneous calls and data on CDMA phones. Probably for power reasons, the LTE chip is disabled.

 

[realeric]

Some South Korea's carriers already launched VoLTE service. AT&T and Verizon will start VoLTE in 2012 or 2013. What is the issue?

Pros:

• HD(Wideband) Voice + LTE Data, simultaneous.
• Unlimited calling, unlimited text.

Cons:

• Unlimited calling & text doesn't mean free. VoLTE consumes you data instead.
• You will be forced to switch to a Data Share Plan (i.e., AT&T Mobile Share Plan or Verizon Share Everything Plan).
• A lot of dropped calls when you move into 3G territory from LTE territory.

 

[dccorona]

Why does LTE radio need to be turned off? That's the part I do not understand. Is it a technical problem? Hardware limitation? Wont they have to disclose that to those who assume they get LTE speeds while tethering and if a long voice call takes place they will be downgraded to 3G data?

it's a limitation on their (ATT's) end. They don't support a device being connected to their network multiple times, but that's just what would be happening if you were on 3G for voice while on LTE for a call. Why this is, I don't know, but I can imagine that the complexity of a system that allows multiple connections simultaneously from a single phone would become unwieldy.

So, until they can do voice over LTE, they have to force you back to 3G when on calls