Quote: Originally Posted by
JonDubya 
What you said is true, but he said specifically "it doesn't know where to look for sats." WHERE they are, not WHICH sats. to look for. Huge difference.
Since the gps satellites are in geosynchronous orbit, they are stationary in relation to the earth. And since each satellite is always in the same orbit and position, then the satellite's position (WHERE) also determines WHICH satellite you're looking at. The only thing changing here is the observer's position. That's why it's so important to initialize your receiver to your current position, so that it can find available satellites to compute a fix. Their WHERE and their WHICH are synonomous. So again I say what EricE said is correct from the perspective of the receiver, and can hardly be called "the biggest crock of **** I've ever heard", unless you've led a very sheltered life.