Why does 3G use so much battery?

[MrBojenglz]

Forgive me if this has been addressed somewhere but there's a ton of threads that say 3g and battery so I couldn't find what I was looking for.

Anyway, WHY does 3G use so much battery? I can see why if I'm on the internet or downloading files etc but when it's simply on in the background not doing a thing, why does that drain the battery so much??

 

[NKT]

You may think your phone isn't doing anything, but it is. It's talking to the cell/cells, managing that connection, checking for pages, etc.

 

[Bswartz95]

Watch the "D" or the arrows under the 3g symbol. Mine seems to be transferring data quite often. Probably more than it should.

Factor in a low signal, and it will really drain your battery.