Date Added: Oct 2012
There are several error sources that cause the estimated position and time measuring from Global Positioning System (GPS) receivers to be inaccurate. The most significant error sources are the satellite clock drifts, mismodeling of gravitational and non-gravitational forces in combining the orbits, geometry of the satellites, ionospheric and tropospheric atmospheric delays, multipath, antenna phase variations, and noise generated with the receiver itself. The receiver accuracy that can be obtained by the GPS observations depends on the authors' ability to account for these errors and the processing techniques. In this paper, they are going to introduce the atmospheric error sources in details and its influences on the received signals the proposed solutions to overcome its effectiveness on the overall GPS system performance.