| It is not where in the world you are that matters. It is where you are with respect to a reference point whether on land or at sea. That is the basis behind Differencing GPS. Utilizing the carrier wave and Gold Code (GC) signal transmitted by GPS satellites, this project uses two GPS receivers and a system integration manager utilizing neural networks and expert systems to determine a user position and speed relative to a fixed point on earth. Two methods of determining the user position are employed: classic triangulation and measuring the difference in the Doppler shift of the carrier wave between the user and the reference receiver. The idea is for the user to know where they are in relationship to a designated fixed point and navigate with respect to that fixed point. The user could range from a farmer or an aircraft out at sea attempting to land on the deck of a carrier. |
