Does Gingerbread use extra battery power to make calls when the phone has poor signal?

Question

Since I got this phone (Galaxy S, originally on Eclair, then Froyo) and switched network provider, I've had major problems with the signal at home, and call quality as a result.

Following the upgrade to Gingerbread, it seems to be behaving differently. I notice that I can have no bars of signal but then on attempting to make a call and connecting it shoots up to 3/4.

Checking the battery usage graph afterwards shows that voice calls (around 5 minutes worth) used 32% of the total battery usage, with display at 34% when it's usually at a much higher percentage.

Is this a feature of Gingerbread? And if that is the case, is there a way to turn it off? Sure, it's useful as it makes for clearer calls when the network is being a PITA, but it's also masking the problem the network is suffering from and as such may prevent me from being able to get out of the contract under the Ts & Cs of their provision of services. (I'd quite like to get out of my contract, so I could get a Galaxy S 2, with its extra power...)

The other side of it, is although it helps with calls, it doesn't help with receiving of text messages, so I'd really rather the network's flaws were fully exposed so I could switch to a provider with whom I could actually use my phone properly.

Answer 1

I would assume this is due to the cell radio firmware, not Android. But I'm not sure. In many cases you can flash older Modem firmware using Odin or Clockworkmod, so you could test and see if the Froyo firmware affects this under Gingerbread. There should be a thread in the Galaxy S forum on XDA with the modems, I'll update this if I remember to look for it later.

Answer 2

Yes, your Gingerbread phone does this, and no, it's not a feature of Gingerbread. This isn't an Android-specific behaviour at all: it's part of the GSM protocol itself, so all phones do it.

When the cell tower transmits, it says the transmit strength in the signal. The phone then works out how much attentuation there is (i.e. how much weaker the received signal is). The more attentuation, the louder the phone has to transmit to reach the cell tower. This works well regardless of whether the attenuation is caused by objects/buildings between the transmitter and the phone, or just because of distance.

If it didn't do this, it would either have to transmit at full power all the time (which would be very bad for phone battery life), or it would get disconnected owing to the slightest bit of attenuation, even though it has enough power to reach the cell tower. Both of those would be much worse.

Because the details of how strong the transmission should be are specified by the GSM protocol, it's very unlikely that using a different official radio firmware (aka modem firmware) would make a difference. Even if you hacked the radio firmware yourself to disable this behaviour, you wouldn't be using a GSM phone any more, so any "if there's no signal at your house" provision of your contract wouldn't apply.