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Data and voice at same time.

hookbill, I'm still not sure why Thunderbolt, as an LTE device, can't do that, considering LTE was made to provide primarily IP services with voice over IP.

Its not the Lte that allows you its the Chipewyan. There are two chips one for voice, text and 1x data the others for 3g and Lte

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No, I just wasn't aware it could do that. My wife has a TB, I have to have her check it out when she calls tonight.
 
Lte is the 4G version of GSM, Wimax is the 4G version of CDMA, that's why LTE can do voice and data.

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After looking up a few others, I believe the Thunderbolt was supposed to get the upgrade. It probably has to do with the chip. Newer phones may have the upgraded chip to allow the simultaneous capability of the upgraded cdma standard, and they could be testing the functionality on a phone by phone basis to make sure that it works well. I don't blame Verizon. What if its there, but it also eats up battery life, or drops call quality to the point of GSM networks? That's one selling point of cdma is the voice quality is actually slightly better than gsm, well if this drops call quality Verizon may decide its not worth it.

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LTE is actually built using both GSM and CDMA experience.

I wonder if the Thunderbolt is built to use LTE purely for data, and let all voice communications go over regular CDMA. That would be weird, because running a pure LTE network is cheaper in terms of costs per bit delivered. Voice over LTE is about 3 times cheaper compared to GSM and CDMA, according to some sources.
 
LTE is actually built using both GSM and CDMA experience.

I wonder if the Thunderbolt is built to use LTE purely for data, and let all voice communications go over regular CDMA. That would be weird, because running a pure LTE network is cheaper in terms of costs per bit delivered. Voice over LTE is about 3 times cheaper compared to GSM and CDMA, according to some sources.

No, Just doing a quick search reveals Voice and Data will be actually over 3G. The 4G voice/data is just because LTE is basically the 4G version of GSM, so it WILL work on both 3G and 4G.

Apparently the latest upgrade to CDMA technology allows for Voice and Data simultaneously over a CDMA network (finally!). I can't tell you the number of people I've talked to who think CDMA is "old" technology, only because GSM allows voice and data at the same time. Its not old, its just a different technology.

I remember reading up on Cellular technologies on Wikipedia and as I was reading, I discovered 4G (this was back when it was only in the theory and design phase, 3G was still the ultimate network). I realized that LTE is the 4G version of GSM, while WIMAX is the 4G version of CDMA. I could be slightly wrong on the CDMA point, but LTE is definitely in the 3GPP family, which includes all 2G and 3G GSM technologies. And since LTE is the 4G version of GSM, it allows for voice and data at the same time.
 
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CDMA (not CDMA2000) and GSM aren't really in the same “department”. If we're comparing CDMA (itself) with something GSM-wise, it'll be TDMA, the underlying access method for GSM networks.

VZW uses CDMA2000 + LTE, I guess. So if they only want to run LTE for data, it's their own choice, which I just find a bit weird.

LTE is not an “upgrade” to GSM/UMTS base stations, it requires building a whole new network; and there are carriers who have no 2G/3G towers at all, yet they deploy LTE with voice over 4G.
 
CDMA (not CDMA2000) and GSM aren't really in the same “department”. If we're comparing CDMA (itself) with something GSM-wise, it'll be TDMA, the underlying access method for GSM networks.

VZW uses CDMA2000 + LTE, I guess. So if they only want to run LTE for data, it's their own choice, which I just find a bit weird.

LTE is not an “upgrade” to GSM/UMTS base stations, it requires building a whole new network; and there are carriers who have no 2G/3G towers at all, yet they deploy LTE with voice over 4G.

I'm not calling it an upgrade, as I'm aware its a completely different network, but I mean inasmuch as 3G GSM/UMTS was an upgrade to 2G GSM/UMTS, so is the same with LTE. I'm just saying that its in the same family of technologies.

Its a little hard for me to find the same articles I read back then, as this was back before Verizon even chose LTE as their 4G network, but there WAS a different technology that was the 4G version of CDMA. But LTE IS GSM, all the difference between CDMA and GSM really boils down to how it shares all of its users in the same frequency, on the same tower.
 
hookbill, I'm still not sure why Thunderbolt, as an LTE device, can't do that, considering LTE was made to provide primarily IP services with voice over IP.

Thunderbolt does it here in lansing michigan. It even worked on 3g before we got lte. That in itself made it my favorite phone. Fyi wifi is not required to do data and voice simultaneously on the tbolt

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CDMA is not really old technology compared to GSM. They are just built differently. CDMA has 2 different type of signaling, which are voice and data. Each signal is fully optimized for respective purpose.

You will be very annoyed if there's frequently break up. Voice signaling uses very low data rate and works well under low SNR. It doesn't even require automatic gain control. Therefore, you can talk well while driving at 100mph.

Data signaling packs so much data into same bandwidth. This requires good conditioning of radio signal. This requires constant monitoring of radio channel condition, if subscriber is driving or static, if subscriber is in the downtown or in the open field. Though there's no data packet exchanged, radio still needs to monitor and adjust internal circuitary so that received signal is decoded error free. If you transfer chunk of data, this isn't bad at all. However, voice is completely opposite. Very low bit rate but connection lasts very long time compared to data call, which means radio can't be off and many circuits are busy adjusting per channel condition and searching for another base stations. This way modem burns lots of power compared to pure voice call.

LTE has lots of bandwidth to burn but modem kills battery dramatically. It requires great mechanism to monitor channel condition very accurately since it packs so much data in it. it's too expensive to carry only 9.6kbps data over it.
 
tothenet, I'm not sure where exactly do you get this from, but in my home country, most operators don't even use voice channels of CDMA any more.

I can place a full HD video call while driving at 170km/h using NTT DoCoMo, for example. There will be no issues with the call quality.
 
tothenet, I'm not sure where exactly do you get this from, but in my home country, most operators don't even use voice channels of CDMA any more.

I can place a full HD video call while driving at 170km/h using NTT DoCoMo, for example. There will be no issues with the call quality.

At the cost of battery power. I am not saying that's not possible, just that it's not optimal.

For the call quality, VoIP requires lots of trick for example. Packet based data network doesn't fully guarantee QoS, which is especially important for voice call. To mitigate those problems, VoIP duplicates same data over a few packets and also adds some of redundancy, which will help recipient can recover voice data even in worst case.

if subscriber is moving at very high speed, channel condition changes dramatically in fast pace. if phone doesn't monitor channel condition fast enough, there will be error decoding received signal, which lose complete packet since error checking is performed per packet. Of course, NAK is sent to sender but it's too late to wait for re transmission since this will play long silence. Instead, a few redundant packets are send so that at least one frame can arrive safely. Compared to pure voice channel, those are all redundancy, which kills battery.

You can drive 10 ton truck to delivery 1kg parcel.

Anyway, there's technology called SVDO but I don't think Verizon is going to roll out. Simultaneous voice and data will be available for LTE phones only.
 
Well, considering my Droid 2 Global usually can get up to 14 hours on battery power, and my DoCoMo phone does 4+ days with video calls… I wonder about the battery being killed.
 
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