[clevermax]

Originally Posted by srishiva

3G should not consume more power than voice (if you keep talking for that long as consuming data). EDGE will. Also Bluetooth is very low power. Dont know why GPS consumes so much power for just listening, maybe its processor intensive.

I guess we can't fix it like that. 3G may use more power than EDGE if there is poor 3G reception. Otherwise it should be consuming less than EDGE. But these are still higher than standby power usage of WiFi, GPS and BT.

You might have heard people complaining 3G in our place draining battery much quicker than EDGE, can be attributed to poor reception, this is just my thought.

[srishiva]

3G has a very fast power control. It cannot increase the power just because its in weak conditions because it affects other users (spread spectrum CDMA) and will not let it happen.
So you need to check what your phone is doing when the connections are on rather than the connections themselves.

[joslicx]

My Win Phone is always on Wifi at home (and I am not using any data connection with it yet) and it gives excellent battery life (around 4 days). Usage is quite less (as I have signal problems in our area and I use the landline which is cheaper).

I guess Windows has excellent power save features (I think in standby it automatically shuts off wifi and bluetooth). The same is not true with my Android. Even if I switch off data connection and wifi and BT (and minimal use) on the droid it still doesnt go deep into second day. Both phones have comparable battery (1500mAH on Windows Phone and 1520 on the droid). No powersave enabled on both.

[vivekiny2k]

Originally Posted by clevermax

Bluetooth - If it is just kept on with no visibility, it won't consume much power either.

I would keep bluetooth out of this analysis because even in standby when I use my bluetooth headset, the phone responds almost immediately. I am pretty sure it keeps polling on bluetooth signal.

[clevermax]

Originally Posted by vivekiny2k

I would keep bluetooth out of this analysis because even in standby when I use my bluetooth headset, the phone responds almost immediately. I am pretty sure it keeps polling on bluetooth signal.

I don't think the phone need to keep polling over BT always. When a paired device like headset is turned on, it can very well initiate a connection with the phone. So it just needs no time to get connected once it is on. I am pretty sure that's the way it works.

[Aroy]

Originally Posted by clevermax

I don't think the phone need to keep polling over BT always. When a paired device like headset is turned on, it can very well initiate a connection with the phone. So it just needs no time to get connected once it is on. I am pretty sure that's the way it works.

I think most wireless devices poll to ensure the connection. You can switch the discovery of new devices off, in that case it will not keep searching for new devices, but then you will not know if there is a device available for pairing.

Ultimately the radios - WiFi, Blue Tooth and GPS are used for utility they give. If you keep them switched off just to save battery, you would have been better off if the phone did not have them. In my case as my primary use is the Phone and not data interchange, I keep the radios off as I do not need them, but as they came with the phone, I do use them once in a while. But for those who need to be in the loop and know where they are and bypass the 3G service for data (when available) the radios are god sent.

[StarrySky]

3G is capable of higher data rates and is also capable of using better codecs for voice traffic. Higher data rates mean more processing and hence a 3G phone will drain the battery faster than a 2G phone. In idle mode, 3G will theoretically provide more standby time than 2G.

[libranof1987]

There seems to be another bug with Mango.

There were times during my recent Kolkata - Ranchi rail travel when there was no network as per the network symbol on the home page and in Settings but I could use internet (GPRS apps like Whatsapp, Facebook) etc.

[StarrySky]

Originally Posted by srishiva

3G should not consume more power than voice (if you keep talking for that long as consuming data).

Voice data rate is in kbps while most 3G phones with HSPA are now capable of supporting data upto 7.2Mbps. Also, if I'm not mistaken, downlink data with HSDPA receives data (and hence requires processing) every 2ms whereas voice packets are received every 20ms.

So I don't think voice data is going to consume same power (battery power) as data traffic if they are used for the same length of time.

[clevermax]

Originally Posted by Aroy

I think most wireless devices poll to ensure the connection. You can switch the discovery of new devices off, in that case it will not keep searching for new devices, but then you will not know if there is a device available for pairing.
.

No, while your Bluetooth is not visible, it doesn't always look for devices by polling. When your paired headset is turned on, it initiates a connection with the paired phone (it knows which one of course) as the master device, and then after connecting, the roles get transferred - phone becomes master.

[vivekiny2k]

Originally Posted by clevermax

No, while your Bluetooth is not visible, it doesn't always look for devices by polling. When your paired headset is turned on, it initiates a connection with the paired phone (it knows which one of course) as the master device, and then after connecting, the roles get transferred - phone becomes master.

There is no way a device can wake up another wirelessly without the other one polling for a signal. It sends signals and hopes the receiver is looking for it. Paired or not is immaterial.

Just so we are clear, I am saying bluetooth wakes up the phone even when it's in standby, which mean it really is not sleeping, but continually polling.

Hard wired connection is a different story where the cellphones can afford to sleep without having to look for anything.

[vikram_d]

Interesting information on Bluetooth power usage.

The initial state is that all Bluetooth devices are in STANDBY mode. In STANDBY mode, the devices, which are un-connected, listen periodically for messages. (Every 1.28 sec). When a unit wakes up, it listens on a set of 32 hop frequencies defined for that unit.

Any |Device can initiate a connection procedure. This device then becomes the master. A connection is initiated by a PAGE message in the case of a known address, or in the case of an unknown address by an INQUIRY message, which is followed by a subsequent PAGE message.

The Page state has several stages. At the beginning the master unit will send a train of 16 identical page messages on 16 different hop frequencies defined for the device to be paged (slave unit). In the case of no response, the master transmits another train on the remaining 16 hop frequencies in the wake-up sequence. It is devised in a way that the maximum delay before the master reaches the slave is twice the wakeup period (2.56 sec). The average delay stands on half the wakeup period (0.64 sec).

The typical use of the INQUIRY message is for finding other Bluetooth devices, such as printers, fax machines or other devices with an unknown address. The INQUIRY message is very similar to the page message, but may require an additional train period.

There are three power saving modes HOLD, SNIFF & PARK. These modes allow power saving of piconet members which are currently not active. If no data needs to be transmitted, the master can put slaves into HOLD. In this mode the internal only timer of the slave runs and no transmissions are made.

A slave unit can also request to be put into HOLD mode. Data transfer can resume when the slave device transitions out of HOLD mode. The HOLD enables the connecting of several piconets or managing a low power device such as a temperature sensor.

The SNIFF mode is used in a way the slave device listens to the piconet at reduced rate. Therefore its duty cycle reduces. Each time interval the slave wakes up and �SNIFF� the piconet. This interval is programmable and depends on the application.

The PARK mode keeps the device synchronized to the piconet but disables its participation in the traffic. Parked devices have given up their MAC address. They can still listen periodically to the traffic of the master to re-synchronize and check on broadcast messages.

If we list the modes in increasing order of power efficiency, there order will be SNIFF, HOLD and PARK mode with the lowest duty cycle.

Source: What is BlueTooth

Edit: I think we guys are going way off topic with all this bluetooth chatter.

[motorworks]

Folks, need some urgent advice! My wife is looking for a new phone and we were looking at the Nokia Lumia 710. The reason I looked at a windows phone is simply because I havent had a great experience with my android phones. My sony ericsson xperia x10 was absolutely pathetic, even after replacement of mother board and the phone itself. I currently have a samsung galaxy ace and even it has a lot of glitches in spite of me not using it much and not downloading a lot of apps either. Anyways, my primary phone is a BB and so its not much of an issue. But the point is that I wanted to stay away from android because of these experiences. The only option other than this seemed to be a windows phone. My wife is not so much in to applications etc, but loves listen to music, take photos etc. But from what I have heard, data transfer in any windows phone is not that easy. You need to upload things to skydrive and then transfer to the phone or something. I'm not sure of this.
Also, my apprehension stems from the fact that both our office laptops cannot take any external appplications because of office restrictions. So without downloading zune application or whatever is required, how do can I transfer files to a windows or from a windows phone?
Please help as I need to buy this today. I also did look at HTC one as an alternative, its got 4.0, but I'm not sure about Android at all.

[DevilsCry]

Originally Posted by motorworks

But from what I have heard, data transfer in any windows phone is not that easy.

Sync contacts in your old Android with Gmail. Sync WP with Gmail. Simple! Not sure why people try exotic methods like Outlook and stuff. Good old method of transferring from SIM card also works.

Originally Posted by motorworks

So without downloading zune application or whatever is required, how do can I transfer files to a windows or from a windows phone?

Plenty of ways. One is to email the file to yourself. Download the attachment in WP. Though only compatible files can be downloaded. Like pdf, doc, docx, xlsx, ppt etc. With WP 7.5, Zune software on PC is history. No one uses that crap anymore.

[motorworks]

Originally Posted by DevilsCry

Sync contacts in your old Android with Gmail. Sync WP with Gmail. Simple! Not sure why people try exotic methods like Outlook and stuff. Good old method of transferring from SIM card also works.


Plenty of ways. One is to email the file to yourself. Download the attachment in WP. Though only compatible files can be downloaded. Like pdf, doc, docx, xlsx, ppt etc. With WP 7.5, Zune software on PC is history. No one uses that crap anymore.

@ devils cry, thanks for your reply. What about blue tooth? I was told that you cannot transfer files from or to a windows phone. Also, say if you had some music files in mp3 format or whatever, how do you transfer it to the WP?