GPS & Battery Issues

[stellion]

Hi all!

I've been doing a GPS project recently, and noticed that the example code Nokia gives for handling the device GPS module drains the battery like mad (Power consumption on the order of 0.42W). A clean device (after formatting) uses around 0.02W. The battery dies after just few hours.

Does anybody here have some suggestions to the improvements that can be made to lessen the effect of the GPS module on battery life?
Some code modifications? Good practise when using RPositionServer and RPositioner? Does the developer have any control over this?

I used Juice on the device for the power consumption data.

P.S. I just noticed that increasing the update interval doesn't really help :|

[symbianyucca]

you should probably not use the GPS all of the time, for example you could turn it off when your application is not in the focus, thus you woudln't be consuming any additional energy then.

[stellion]

This is one of the workarounds, however I need GPS positions at percise (or as percise as possible) times. So sometimes when locking onto GPS satelites takes a lot of time, it will cause me to miss out a reading... I will consider locking some time prior to the required readout time, but as a last resort, since my readouts can be frequent thus making this method inefficient...

I was thinking of some other solutions...

[david.caabeiro]

You may want to check this too:
http://www.forum.nokia.com/main/reso...ment/?cp=1007A

[stellion]

Thanks for the link. Some valuable reading there.
I'm playing around with the RPositioner & RPositionServer classes and noticed that decreasing the callback time (ranging from 5seconds to 300seconds), doesn't change the power usage. Found this quite eerie.

If I understand the whole Location Framework correctly executing Open() on a RPositioner instance is the moment the GPS module starts the whole locking to satellites procedure, right?