Searching for signal

[Aimster]

Was in the basement at work today.
My iphone was half dead when I left work. I didnt even use it.

Does searching for a signal use up more battery than having a signal?

 

[BassBomb]

yes

 

[Aimster]

Curious as to why that is.
Isn't it just a ping to see if it picks up anything?
Then when it does pick up a signal is it not still pinging?

 

[pm]

One of the big goals of the circuitry in the radio on any cell phone is to find the closest tower to itself and identify itself to it. The power output of the GSM transceiver varies depending on how far you are to the tower. When the cell phone is hunting for a signal, it's constantly searching at the maximum power looking for the tower. If you have a very strong signal, then the cell phone doesn't check as often for the tower, and when it does, it uses the lowest power setting. If you have a weak signal, it will use more power. Worst-case is to have no signal at all, at which point it searches frequently using the strongest power setting.

 

[DivideBYZero]

Wot pm said *2

 

[gorcorps]

Turn on airplane mode on your iphone when you know you're in a no-signal area and won't need your phone right away.