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Why does 4g drain so much more?

H

hurricane630

Well-Known Member
I'm just curious, but why does 4g drain so much more than 3g? is it that there aren't as many towers for 4g??

Also what's the reason wifi saves so much battery? EX: my phone 16 hours off charger and still at 60%, all on wifi with 1.5 hour screen time.
 
hurricane630 said:
I'm just curious, but why does 4g drain so much more than 3g? is it that there aren't as many towers for 4g??

Also what's the reason wifi saves so much battery? EX: my phone 16 hours off charger and still at 60%, all on wifi with 1.5 hour screen time.
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4g (and even 3g) consumes more power than wifi because the power involved in boosting the signal is much higher. Think about it in terms of distance (to simplify things). When your phone talks to a wifi router, you're talking 10's or maybe 100's of feet. 3G/4G is 1000's+ of feet. Also, wifi RF devices have had years to mature and optimize and use the latest silicon process technology. That's why 3G is more efficient than 4G, for the most part. 3G radios are very mature, have been power optimized and are using the latest process technology. I suspect 4G radios will see a significant improvement once 2nd generation LTE radios are designed on newer process technologies.

Without getting too much into techie details, a smaller process technology (45nm vs 22nm, etc) means less power consumption, less leakage (standby) power, etc. In fact, Intel's tick/tock model relies on their ability to do process shrinks and basically provide the same performance at a much lower power envelope due to a newer and more power efficient manufacturing process.
 
An article awhile back said Verizon's LTE uses as much power as 3G+Calling at the same time. Something to do with the way the network and devices work right now, it's very inefficient. 3G technology has had a lot of time to mature and become efficient the past couple of years.
 
that cleared that up a lot :)!!
Appreciate you explaining that to me lol I knew the battery life was significantly better on wifi, just wanted some clarification as to why, so thank you!
 
LTE chips in current phones are also first generation; they're very large and power hungry. Next gen phones later this year will have the first second generation LTE chips that will be significantly more efficient.
 
Higher frequency 4G signals have comparatively shorter ranges and poorer building penetration versus lower frequency 3G signals. So in almost all circumstances, the phone will have to boost the 4G signal a greater amount than a 3G signal to communicate with a tower where 3G & 4G antenna are co-located.

This is similar but not identical to how a low frequency AM radio signal can travel great distances and penetrate buildings and terrain -- though at lower fidelity -- versus a higher frequency, higher fidelity FM radio signal that is more-or-less line-of-sight, and prone to interference.
 
I thought VZW LTE frequency was 700MHZ? An overlooked reason why LTE right now eats more is because that radio as well as the 3G radio are on at the same time. When you turn LTE off only one radio is up and running and being powered. When it is on it uses both for when LTE drops out. Which is also why with LTE on you can call and surf at the same time.
 
An EE I work with indicated to me that LTE encoding/decoding was done in software, not in the hardware, and that was one of the reasons LTE is so inefficient at the moment.

Anyone know if that's true?
 
Technically, 4G data transfer is more efficient, its just that, as mentioned, we are still very early on in the game and the hardware is not. With newer chips they will be more efficient. I also read that we currently have two separate chips, one for 3G and one for 4G thus making it even less efficient. The next generation of hardware is supposed to include hybrid 3G/4G chips which should also increase efficiency.

As for why Wifi is so much better....I don't know technically speaking, but I would be willing to bet that it takes way less power to push data 35ft across the room than 3500ft down the street....
 
byrds8 said:
I thought VZW LTE frequency was 700MHZ? An overlooked reason why LTE right now eats more is because that radio as well as the 3G radio are on at the same time. When you turn LTE off only one radio is up and running and being powered. When it is on it uses both for when LTE drops out. Which is also why with LTE on you can call and surf at the same time.
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Your Nexus maintains a 1xRTT connection for voice calls while on 4G data but I don't believe a 3G data connection is active concurrently -- explaining why the switching time between 3G and 4G takes so long.

In the past Verizon has talked about moving to a voice over LTE Staten, enabling it to shut of the other radio(s), but I don't know what the status of that is.
 
Voice over LTE will happen in the future but none of the current Verizon LTE phones except the LG Revolution will support it.
 
dguy said:
Voice over LTE will happen in the future but none of the current Verizon LTE phones except the LG Revolution will support it.
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I realize this is getting off topic, but with respect to voice over LTE and the LG Revolution, it does it as a data service, not unlike Skype. It can't hand off to the 1x if the data connection is lost.

I believe it is (was?) Verizon's intention to roll out a stand-alone voice over LTE that can hand off as needed, but also read that with the decline in voice call usage and revenues, this technology has been moved down the priority list, due to the development and roll-out costs, and expected low return on investment.
 
what are the bars in the triangle showing?

since moving to the 4.0.4 radios I have tried 4g, then 3g only, now back to 4g

when I was on 3g only I would typically see 1 or 2, max 3 bars at my home

now that I'm back on 4g I see 3 or 4 bars, min 2 bars in the same spot

are the bars a true representation or should I not get caught up in looking at them?
 
ignore the bars. If you want to know the true signal strength you can either go to "about phone" in the settings menu or download a signal meter widget....but some of them don't work with 4G. I found 1 that did but I can't remember which one.
 
Tim K said:
ignore the bars. If you want to know the true signal strength you can either go to "about phone" in the settings menu or download a signal meter widget....but some of them don't work with 4G. I found 1 that did but I can't remember which one.
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Sensorly. :)
 
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