A-GPS, bug or feature?

[gian]

hello All,

my GPS does not track satellites if I have no network connection.

I understand that A means "assisted", so I guess this is a feature.

It's pretty pointless to have a GPS you can't use on the sea, or abroad, if you set no data roaming.

Sorry if the question sounds silly, but is there a way to get it working without assistance?

thanks for reading,

-Gian

[schout]

http://en.wikipedia.org/wiki/Assisted_GPS

In short: aGPS uses your dataplan to get your position.

             Your mobile connects to a server, and that server provides the GPS information.

And I wouldn't rely on a smartphone or any other mainstream GPS out in the open sea.

GPS-satalites are always off by a couple of degrees, cliffs aren't

[meik61]

Yes, there is a way to get GPS with no assistance, but you need to be patient. When there is no data connection, the time to the first GPS fix is so long that programs like Google Maps give up before you get your fix.

I worked around this by using the "GPS Status" app (https://play.google.com/store/apps/details?id=com.eclipsim.gpsstatus2). How to use:

1. turn on GPS
2. start "GPS status", watch satellites showing up in status display
3. after you get a GPS fix (typically takes several minutes), terminate GPS status and start your navigation software.

I don't know if this is really necessary, but it works for me, and it has the added benefit that you get information on reception quality / number of satellites. Note that you need good signal from at least four satellites.

GPS accuracy is typically better than a few meters; still I would not attempt to maneuver the Costa Concordia using a mobile phone

[gian]

LOL! thank you both for your advice and sound recommendations!

I promise I won't use it to pilot a supertank through narrow straits!

I was on a ferry this summer, and wanted to follow the navigation with my GPS.

I guess I was not patient enough because I do have GPS Status installed, and could see some sats, but it was not tracking.