Battery Life after LTE went live. - Sprint HTC EVO 4G LTE

I live in Houston and have been able to pick up 4G since Friday. Ever since then I have noticed that my battery life has not been as good as it was before 4G went life. I used to be able to make it the full day without recharging but now im only getting a little over half a day.
This used to happen with my OG EVO thats why I always kept 4G off on that phone.
I have full 4G bars at my house but in downtown where I work its very spoty. I am guessing the battery drain is coming from the constant cycling between 3G and 4G.
Has anyone else seen a decrease in battery life after 4G went live?

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O.LPZ81 said:
I live in Houston and have been able to pick up 4G since Friday. Ever since then I have noticed that my battery life has not been as good as it was before 4G went life. I used to be able to make it the full day without recharging but now im only getting a little over half a day.
This used to happen with my OG EVO thats why I always kept 4G off on that phone.
I have full 4G bars at my house but in downtown where I work its very spoty. I am guessing the battery drain is coming from the constant cycling between 3G and 4G.
Has anyone else seen a decrease in battery life after 4G went live?
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One thing I have noticed about mine (I don't have LTE yet, BTW), is that I don't have a switch like I used to with my EVO 3D. Is there a way to turn it off? I'd assume that if you're running LTE all day long, you're probably going to burn more battery than normal.

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eXplicit815 said:
One thing I have noticed about mine (I don't have LTE yet, BTW), is that I don't have a switch like I used to with my EVO 3D. Is there a way to turn it off? I'd assume that if you're running LTE all day long, you're probably going to burn more battery than normal.
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Settings, mobile network, change from CDMA/LTE to CDMA only

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go in to settings, click on mobile network, then select cdma only if you only want 3G... I've found that you have to do that everytime you restart, for some reason it doesnt remember

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painkillaz said:
Settings, mobile network, change from CDMA/LTE to CDMA only
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iamkoza said:
go in to settings, click on mobile network, then select cdma only if you only want 3G... I've found that you have to do that everytime you restart, for some reason it doesnt remember
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So, it's not just as easy as it used to be. I'm sure they'll run out an update with a switch like they used to have. That'd be ideal. You would think they would've put it in that last update.

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eXplicit815 said:
So, it's not just as easy as it used to be. I'm sure they'll run out an update with a switch like they used to have. That'd be ideal. You would think they would've put it in that last update.
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I'd imagine they didn't include a toggle widget because they are selling this phone in areas where the 4G LTE rollout isn't even scheduled yet (i.e. beyond 2014).... if you give people a widget for 4G, it will just make them unhappy it doesnt work...

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I was able to test out 4G in Kansas City for the first time yesterday for about 45 minutes and I thought it used less battery than 3G does. I was at a restaurant and while I was waiting for my food I ran speed tests (highest was about 10,000 kbps and my dad actually got around 9,000 kbps on wimax on his OG evo) and downloaded two 25MB games. It downloaded faster than my wifi... I left it on while I ate for about 30 min. and it was still at the same battery percentage when I started to use it again. It's probably draining a lot because of the cycling between 3G and 4G.
Sorry about the rambling.

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It's definitely draining faster if its cycling between 3G and 4G.
It's been discussed before but the logical reason behind there being no actual toggle widget for LTE is because a. It doesn't drain as much as WiMAX did because the radio is built into the soc and not separate so shutting it off completely isn't so much of an issue to save battery. If you wanna save a little extra juice you can stop the radio from searching for an LTE signal through the settings. The other reason is LTE unlike WiMAX is being built to be your permanent connection unless you have to fallback to 3G. It will have better coverage and penetration. It's not a supplement like WiMAX was. Not saying WiMAX couldn't have been but based on the frequency it is on and the way it rolled out it just never happened that way.
Sent from my EVO using xda app-developers app

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Also keep in mind that not all towers have LTE on them so your phone may have to use more juice to reach the spread out towers. It will get better with time as all the towers are scheduled to get LTE.
Sent from my C64 w/Epyx FastLoad cartridge

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4G is a much larger battery drain than 3G. Ask anyone with a Verizon phone. Using the LTE is obviously going to empty your battery faster.

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The S4 SoC contains a programmable world modem and zero radios. That's straight from the Qualcomm literature that anyone can download.
That Qualcomm processors contain radios is an urban myth perpetuated by uninformed blog writers and has been going on for over two years.
The radio transceivers are separate and housed in separate chips (usually more than one transceiver per chip). When properly controlled, radios are basically shut down when not in use.
Because all voice is on CDMA, it's a reasonable expectation to lose a bit more power when talking and downloading via 4G at the same time.

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SoraX64 said:
4G is a much larger battery drain than 3G. Ask anyone with a Verizon phone. Using the LTE is obviously going to empty your battery faster.
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4G on this phone will possibly drain your battery a little faster than 3G (i mean a little). The S4 has the LTE radio built in to the chip so it's pretty much powered all the time, but not active. The Thunderbolt(example Verizon phone) contains the S2 which doesn't have it built in so it requires a separate antenna which will require more space and more battery. Only cycling between the technologies will cause the battery to drain the most.

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bobarune said:
4G on this phone will possibly drain your battery a little faster than 3G (i mean a little). The S4 has the LTE radio built in to the chip so it's pretty much powered all the time, but not active.
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No.
The S4 chip contains zero radios. Please see my post above yours.
The Thunderbolt(example Verizon phone) contains the S2 which doesn't have it built in so it requires a separate antenna which will require more space and more battery.
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In addition to a separate radio for LTE, the Thunderbolt needed an additional LTE modem, because the S2 in the Thunderbolt had only the CDMA and GSM modems built-in.
Liike all Qualcomm chips, it had ZERO radios built in.
Only cycling between the technologies will cause the battery to drain the most.
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Yep.
View attachment QU_SnapdragonS4_White_Paper_FNL_Rev6.pdf
View attachment snapdragon-s4-product-overview.pdf
View attachment snapdragon-specs.pdf
Modems, yes. ZERO radios. None. Nada. Zip.
The counting of the radios in the S4 shall be zero and zero shall be the counting of the radios in the S4.

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EarlyMon said:
No.
The S4 chip contains zero radios. Please see my post above yours.
In addition to a separate radio for LTE, the Thunderbolt needed an additional LTE modem, because the S2 in the Thunderbolt had only the CDMA and GSM modems built-in.
Liike all Qualcomm chips, it had ZERO radios built in.
Yep.
View attachment 1204839
View attachment 1204840
View attachment 1204841
Modems, yes. ZERO radios. None. Nada. Zip.
The counting of the radios in the S4 shall be zero and zero shall be the counting of the radios in the S4.
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Thanks for the links and clarification. However I think the point at hand is the S4 was designed with LTE in mind and helps conserve battery when compared to other SoC's on the market. I believe the Exynos is currently the only other LTE compliant SoC however if I'm not mistaken due to production Samsung only used them for the korean SIII. Regardless using 4G will cause more battery drain but compared to older phones the drain will not be as bad thanks to the S4. And if the phone is constantly switching connections it will drain even faster.

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Cordy said:
Thanks for the links and clarification. However I think the point at hand is the S4 was designed with LTE in mind and helps conserve battery when compared to other SoC's on the market. I believe the Exynos is currently the only other LTE compliant SoC however if I'm not mistaken due to production Samsung only used them for the korean SIII. Regardless using 4G will cause more battery drain but compared to older phones the drain will not be as bad thanks to the S4. And if the phone is constantly switching connections it will drain even faster.
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Yes, the S4 is more power efficient for LTE because it doesn't require one more modem chip in addition to the radios.
My point in clarifying is that people are over-estimating the power budget by thinking that separate radios are not in play.
If trying to wrap one's arms around performance as a function of tech (something I completely support), it's important to not be misled by the unwashed news bloggers on the tech side.
As for the Korean SGS3 LTE model, it contains a separate LTE modem chip, at higher cost and complexity along with lower reliability and battery efficiency.
http://www.theverge.com/2012/6/24/3115367/south-korean-galaxy-s-iii-quad-core-lte
Expect to see Samsung processors with embedded LTE modems in the near future.

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I don't understand why LTE would be a larger drain. If it is a newer technology, and the phone was built with the prime directive of utilizing a 4g network. Shouldn't it create optimal battery life when locked on "LTE only"?

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gdrocks said:
I don't understand why LTE would be a larger drain. If it is a newer technology, and the phone was built with the prime directive of utilizing a 4g network. Shouldn't it create optimal battery life when locked on "LTE only"?
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LTE only isn't an (easy) option, you still need the CDMA radio active for voice.
Someday, according to a statement by Dan Hesse, we will get SVLTE - simultaneous LTE voice and data. Then we can roll LTE only.
The target is get the LTE system power efficiency as high as possible.
PS -
All of the HTC WiMax phones used the exact same Sequans radio SoC, built on older, power thirsty 65 nm chip technology.
Can't get details without a proper teardown (and I spent the morning this > < close to tearing mine down, but I couldn't get a good macro photography rig set up) we can't know the actual chip tech used for our radios. I suspect it's state of the current art, though.

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EarlyMon said:
Yes, the S4 is more power efficient for LTE because it doesn't require one more modem chip in addition to the radios.
My point in clarifying is that people are over-estimating the power budget by thinking that separate radios are not in play.
If trying to wrap one's arms around performance as a function of tech (something I completely support), it's important to not be misled by the unwashed news bloggers on the tech side.
As for the Korean SGS3 LTE model, it contains a separate LTE modem chip, at higher cost and complexity along with lower reliability and battery efficiency.
http://www.theverge.com/2012/6/24/3115367/south-korean-galaxy-s-iii-quad-core-lte
Expect to see Samsung processors with embedded LTE modems in the near future.
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Ok, once again thanks for the clarification. It'll be interesting to see Qualcomm's answer to those chips since both Samsung and Nvidia will have quad-core SoC's with LTE modems in the near future.
gdrocks said:
I don't understand why LTE would be a larger drain. If it is a newer technology, and the phone was built with the prime directive of utilizing a 4g network. Shouldn't it create optimal battery life when locked on "LTE only"?
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To add to EarlyMon's response. Another reason would be 4G requires more power because of the higher bandwidth. Even though the SoC is designed to support it by nature the higher bandwidth going through the phones has a higher power draw. It's just not as bad as it could be because the technology is evolving to accommodate it. Again e.g look at the Thunderbolt and a lot of early Verizon LTE phones. The technology wasn't quite there yet and the phones battery life was abysmal. As the technology evolves the battery life gets better.

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Than what do they mean by "integrated" they constantly use it when referring to lte on the chip, also i read in one of those links that there lte chip Supports multiple lte 4g, 3g, & 2g frequencies so does that mean when sprint swiches lte over to the iden network frequency that are phones will be compatible via a software update?
Sent from my EVO using xda app-developers app

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noneed2aim said:
Than what do they mean by "integrated" they constantly use it when referring to lte on the chip, also i read in one of those links that there lte chip Supports multiple lte 4g, 3g, & 2g frequencies so does that mean when sprint swiches lte over to the iden network frequency that are phones will be compatible via a software update?
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Check out these two diagrams, first is the S4, second is the Tegra 3 -
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Note that big block, upper left, on the S4 - lots of mobile radio technology _support_ is integrated, that's largely or completely missing on other processors.
The world modem is programmable, so instead of lots of unique separate chips depending on the carrier, they just program that block as needed.
As for whether or not our LTE radios can handle the upcoming 800 MHz operations, I can't say (don't know) but here's what would be required - either a programmable radio, or a radio with the function there but unused, and if either of those are true, then the phone would have to be recertified by the FCC to work at the new frequency. And, it would have to work with the existing complement of antennas.
So, I suppose that a firmware update is possible, but I don't know.