[AC Question]

I have droid turbo 2. When someone calls my data shuts off. Very annoying when I have maps app up and it looses connection. Or some times someone calls and asks something that need to look online to see the answer, can't while on the phone. I have to hang up, check it out and then call back. But at home I have wifi and can use the phone and wifi internet.

[dpham00]

You need to have advanced calling 1.0 enabled on your account and on the phone itself.

Then on 4GLTE, you can simultaneously do calls over lte (volte) and data.

If you are not on lte then you cannot do simultaneous voice and data on the turbo 2.

[CharlesH]

You need to have advanced calling 1.0 enabled on your account and on the phone itself.

Then on 4GLTE, you can simultaneously do calls over lte (volte) and data.

If you are not on lte then you cannot do simultaneous voice and data on the turbo 2.

Nor on an iPhone or pretty much all current Android LTE phones. Up until a year or two ago, Android LTE phones which supported CDMA (like for Verizon) had the hardware to support simultaneous use of CDMA for voice and LTE for data. No more. The Verizon version of 3G does not support voice. This is not an issue for GSM-based systems like at&t and T-mobile, since their version of 3G supports both voice and data.

[Jaingo5150]

I was under the impression it had more to do with single radios now being used in some handsets, and not a new Verizon standard. Is that wrong?

Posted via the Android Central App

[doogald]

I was under the impression it had more to do with single radios now being used in some handsets, and not a new Verizon standard. Is that wrong?

Yes and no. From the beginning, CDMA (as implemented by Verizon*) does not have enough bandwidth to carry mobile data (using EVDO) and voice at the same time. When Verizon added LTE, they had a single radio with two antenna connections, and the radio would quickly switch between CDMA for calls and LTE for data as long as you had an LTE connection while you were on a call. Most phones since 2014, however, dropped the second antenna - I believe in part because it draws more battery power and I think gives worse performance, plus it's a more complicated design - when they added support for Voice over LTE ("Advanced Calling".)

I have been very underwhelmed by Advanced Calling - it's never worked anytime I've had it turned on, so I just don't bother using it unless I am traveling somewhere when I need navigation.

See http://bits.blogs.nytimes.com/2012/0...-5-calls-data/ for a little more background.


--
* There is a standard for CDMA called SVDO that could do simultaneous voice and data, but I believe Verizon only implemented in the HTC Thunderbolt. They knew that they were rolling out LTE at the time so I think just didn't want to bother with SVDO beyond that phone.

[dpham00]

Nor on an iPhone or pretty much all current Android LTE phones. Up until a year or two ago, Android LTE phones which supported CDMA (like for Verizon) had the hardware to support simultaneous use of CDMA for voice and LTE for data. No more. The Verizon version of 3G does not support voice. This is not an issue for GSM-based systems like at&t and T-mobile, since their version of 3G supports both voice and data.

The reason is because Verizon was cheap and didn't want to make phones with two cellular paths. TMobile and att only have one cellular path. The early Verizon 4GLTE phones like the Thunderbolt and s3 had a separate cellular path for the cdma voice and thus was able to support simultaneous voice and data over 3g(evdo) and lte. From the note 2 to the note 4, they had simultaneous voice and data but only over lte. After the note 4, you needed volte to get simultaneous voice and data over lte.

You are correct in that gsm carriers like att and tmobile can do simultaneous voice and data on 3g(h/h+) . 4GLTE requires volte for simultaneous voice and data. If the phone or gsm carrier doesn't support volte then you will drop to h/h+ when making calls.

[dpham00]

Yes and no. From the beginning, CDMA (as implemented by Verizon*) does not have enough bandwidth to carry mobile data (using EVDO) and voice at the same time. When Verizon added LTE, they had a single radio with two antenna connections, and the radio would quickly switch between CDMA for calls and LTE for data as long as you had an LTE connection while you were on a call. Most phones since 2014, however, dropped the second antenna - I believe in part because it draws more battery power and I think gives worse performance, plus it's a more complicated design - when they added support for Voice over LTE ("Advanced Calling".)

I have been very underwhelmed by Advanced Calling - it's never worked anytime I've had it turned on, so I just don't bother using it unless I am traveling somewhere when I need navigation.

See http://bits.blogs.nytimes.com/2012/0...-5-calls-data/ for a little more background.


--
* There is a standard for CDMA called SVDO that could do simultaneous voice and data, but I believe Verizon only implemented in the HTC Thunderbolt. They knew that they were rolling out LTE at the time so I think just didn't want to bother with SVDO beyond that phone.

I think that you are confusing cellular paths with antennas. The 4GLTE devices even the iPhone has at least 2 cellular antennas, however devices after 2014 only had one cellular path (but still has more than one antenna)

My old rezound and s3 also supported svdo. There could be other devices, but I am not sure.

[dpham00]

Thunderbolt


Verizon note 4

[doogald]

I think that you are confusing cellular paths with antennas.

Yep, cellular paths, thanks for the correction. The result is the same. I'm not sure why they stopped this: the phones were more complicated to design? Qualcomm stopped making the radios that supported this design? The power effects? Verizon wishing to market their VoLTE service? A combination of these?

Does Sprint have simultaneous voice and data over CDMA/LTE on any of their phones at this point?

[dpham00]

Yep, cellular paths, thanks for the correction. The result is the same. I'm not sure why they stopped this: the phones were more complicated to design? Qualcomm stopped making the radios that supported this design? The power effects? Verizon wishing to market their VoLTE service? A combination of these?

Does Sprint have simultaneous voice and data over CDMA/LTE on any of their phones at this point?

Well it makes the design more complicated (and I am assuming costs more money for Verizon). The launch is also more delayed before... Notice s6 and beyond, Verizon launch is close to other carriers(for the most part)


Power consumption I would imagine would be very slightly worse but the note 4 was pretty good as is


That's why some Verizon phones like the note 4 were physically different than the other carrier versions,because of the additional cellular path.


My understanding is that sprint spark devices require volte for simultaneous voice and data.