Hi, as the title suggests, are their any power savings on a mobile using 800MHz 4g vs 1800MHz and higher frequencies or do they work out around the same?

No network currently has both 800 and 1800 right now so it's hard to say. Comparing between different networks is a bit fishy because of different network configurations, so far I find 800Mhz networks use *more* power.

Ah ok, I was just wondering if the lower frequency would allow a lower transmit power from the handset.

In theory, yes, but because it's different networks operating with different settings and different hardware, it's hard to compare directly.

The rf transmissions of the handset are a pretty minimal part of the power used TBH, so I wouldn't expect the frequency to make any noticeable difference to the overall battery life used.

The power is really used in the signal processing which is independent of the frequency, and is the main reason that LTE takes more juice than 3G, and then 3G more than 2G, e.g the actual maximum handset radio transmission power allowed is actually 4 times higher on GSM than on 3G or 4G.

Well, 2G has a higher instantaneous limit but you can't really compare it since with TDMA and DTX it's only transmitting a fraction of the time, well less than 1/4, so the average RF power output isn't 4 times higher.

Then again most handsets these days are a lot more efficient than before and consume a total of <1w when transcieving on 3G, so the RF can become a significant fraction (30-50%) of the total power consumption.

True enough. 3G power control is also (by necessity) much more aggressive and will always transmit at just above the minimum power required. Quite an interesting paper below, which doesn't split the 2G/3G into RF and other components but does show 3G takes on average twice the power of GSM for a voice call.

If you want to save battery life, a black background is the way to go!

http://www.researchgate.net/profile/...4f1ac8816c.pdf

Especially on OLED / AMOLED screens.

ERM and totally pointless if you have and LCD screen :L

And I'd rater not suffer a constantly degrading screen thanks

Actually you will find all screens degrade after time.....whether SLCD, IPS , AMOLED and so on....

Of course but the difference between a uniform degradation and a patchy smeared mess is quite striking and not something I'm willing to except for £500 +

Also samold screens can show signs of degradation within 2 months of use which is something you just don't find with lcd