GPS: can you lock on to same Satellite?

Hello everyone, I was wondering if anyone has any idea if I can have multiple GPS unit connected to the same Satellites? Or if it is possible to choose the satellites available in view?

Thank You in advance.

Why would you want to do that?


GPS receivers determine which satellites are in view from the almanac data and try to tune to all those that are, locking on to any with a strong enough signal I believe.

Since individual satellites can drop out receivers try to get more than enough in lock, the max number of channels depending on the chipset.

You need 4 satellite signals to get a full fix, more also reduces the error circle as well as increasing robustness to drop-out.

And they are moving too …

thanks for the replies.

I was just wondering if this is possible. I don't have a GPS unit ready at hand, so while going through the sample codes, I was just curious.

Is it possible to have the GPS unit select an available satellite?

thank you

I think they generally lock onto all they can get a signal from. The satellites rotate in an orbit around the earth, they are not stationary (appearing) like a geosynchrous satellite (like satellite TV for example). You can get a message telling you which the unit is using. Read up on the specs for the GPS unit you are interested in. Examples: