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TheIntruder

macrumors 68000
Original poster
Jul 2, 2008
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Does utilizing the 5GHz wi-fi radio consume more power than the 2.4GHz band?

In my wholly unscientific, anecdotal observations, it may.

Aside from comparisons about speed, interference, and range (which 2.4 definitely wins), I'm curious about the power consumption aspect.

The wifi chips inside iPhones aren't as complex as one might find in other devices (the one in my iP5 is apparently single-stream 150Mbps)

I believe iOS prioritizes the selection in favor of the faster network if both are present and available, but I've seen conflicting evidence (it chooses 5GHz at home, 2.4Ghz at the office).
 
I have not noticed a difference.

However if reception is less with one versus the other, the phone will use more power to transmit.

Compared to say 3G, it will still use less power with WiFi than cellular.
 
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Aside from comparisons about speed, interference, and range (which 2.4 definitely wins), I'm curious about the power consumption aspect.

Not sure what you mean by this. The speed between the two should be the same on a theoretical basis. For interference, 2.4GHz is so crowded that any physical benefits the longer waves have are far out weighed when you consider noise from just about every other electronic device on your block. Of the three, I think the only place 2.4 wins is in range, which can be a bad thing when you consider that you have do deal with more noise. And yes, range is theoretically better, but advanced routers do a lot of things, like beam forming, to try and make up for this. I know I have no issues in my single-story home with my AC Airport Extreme.
 
I have not noticed a difference.

However if reception is less with one versus the other, the phone will use more power to transmit.

Compared to say 3G, it will still use less power with WiFi than cellular.

3g/4g is much better now, looking at something like the latest phones (S5/HTC M8) the difference between 4g and Wifi usage are minimal now.

http://www.anandtech.com/show/7903/samsung-galaxy-s-5-review/5

Off course if you have a weak 4G signal your going to have a bad time.

Also I think a 5Ghz signal might be better for battery life has it will have less interruption since most things are on 2.4ghz, off course I have no clue what I'm talking about.
 
Off course if you have a weak 4G signal your going to have a bad time.

Yep, especially if you're out in the sticks and far from a tower.

In rural areas, cel towers are few and far apart, and each covers MUCH larger areas. This is due to the relatively flat terrain, lack of buildings, and low density, meaning each cel has to handle much fewer users. As a result, though, the cel that you are on might be several MILES away, which means your poor little phone has to really crank up the transmit power to reach it.

When I was camping in upstate NY, my iPhone 5's battery life SUCKED. I wasn't even using it that heavily, and found myself having to recharge it with a portable charge pack often! Eventually I started just putting it in airplane mode whenever not using it, which helped quite a bit.
 
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