Multi-monitor station `on the fly´ ambiguity resolution: the impacts of satellite geometry and monitor station geometry

It is noted that resolving the carrier phase cycle ambiguity on the fly is the key to precise (centimeter-level accuracy) real-time differential GPS (Global Positioning System) kinematic positioning. The resolution requires on the fly isolation of the correct ambiguity from the geometric range and the errors and biases in the observations, and therefore it is not an easy task to accomplish. The performance of the ambiguity resolution, however, can be improved by using more than one monitor station along with a reliable on the fly ambiguity resolution technique. The advantages of multimonitor station on the fly ambiguity resolution are described. The impacts of satellite geometry and monitor station geometry on the ambiguity resolution are analyzed, and some results are presented to highlight the important issues. The effects of the geometry of satellites and monitor stations on the on the fly ambiguity resolution were investigated by considering only the observation noises, assuming that all the biases in the observations have been eliminated by applying the corrections derived by the primary monitor stations