How to minimize GPS power consumption

Hi,

We are developing a GPS based tracking software for S60 3rd and 5th editions. In our use case, the phone should send it's location to a web service every five or ten minutes.

As anticipated, power consumption has been quite a challenge. Here's what we have done:
-GPS chip is turned off as soon as the coordinates are available.
-Data connection is closed as soon as new location is sent to server.
-With this method, we are getting only 6-8 hours of battery life. We should get to at least 24 hours.

One of the ideas we found is to use accelerometer to track device movement and get a new GPS location only if the phone has moved significantly since the last fix. Would this be a viable solution?

Any other ideas how to minimize battery consumption?

We've been testing mostly on S60 3rd FP1 (N95 8gb). It seems that with this device, if getting the first GPS fix fails, GPS chip stays on even if it's shut down after failed try. Does anyone know if this has been fixed in 5th edition base devices? In general, what would be the best approach when getting a fix fails? Track phone movement with accelerometer and try again when the phone has moved?

Thanks for your help!

Can it be a solution in your case by using accelerometer since if the phone is moving with constant speed? Also it will take power from phone while we are always checking the acceleration. If you need only rough estimation of location then network based location could be a solution.

[QUOTE=pyykkis;734808]We've been testing mostly on S60 3rd FP1 (N95 8gb). It seems that with this device, if getting the first GPS fix fails, GPS chip stays on even if it's shut down after failed try. Does anyone know if this has been fixed in 5th edition base devices? [/QUOTE]
N95 (and friends i believe) keep chip [I]warm[/I]. In many usecases this is actually quite nice and doesn't cost much power. Check whether power consumption goes down after 30s/60s. If it's that, than I haven't seen this feature since 3.2 anymore, so you should be safe with 5.0 ;).

Hi

We have studied the problem and published several solutions and the accelerometer solution will buy you something.

Have a read of our paper:
Kjaergaard et al. Entracked: energy-efficient robust position tracking for mobile devices
[url]http://scholar.google.dk/scholar?cluster=5573182638466474435&hl=da&as_sdt=2000[/url]

You can find more papers on the issue here:
[url]http://person.au.dk/en/mikkelbk@cs.au.dk/pub[/url]

Hie. I have developed an app for mobile tracking on s60 series cellphone using gps reciecver. I wanted to know two qstns

1) How can I measure the amount of power consumption of my mobile terminal when gps reciever is on?Is there any software availble for this

2)How can I decrease this power consumption as much as possible..

Have you tried to use this Energy profiler (though I have not used it)?
[url]http://www.forum.nokia.com/Library/Tools_and_downloads/Other/Nokia_Energy_Profiler/Quick_start.xhtml[/url]

Whenever you don't need location from GPS, good idea to close it. But you have to compromise with other issues

What is the Average power consumption value when GPS reciever is turned on?

i dont know how you can see de consumption, but there is a way to se de prower consumption.
criteria.setPreferredPowerConsumption(criteria.POWER_USAGE_LOW)

bye !!!