Kinematic GPS: resolving integer ambiguities on the fly

Abstract

In the kinematics GPS (Global Positioning System), the initial integer ambiguity must be resolved either by a static survey over time or by instant calibration with a known baseline or an antenna exchange. It is pointed out that, while these standard methods require the maintenance of a baseline strategy to an Earth-fixed reference frame during the initialization, there are situations when at least one of the receivers may be constantly in motion. Two ideas are proposed for adapting standard kinematic techniques to situations that do not naturally allow for the constraint of a fixed baseline. The first calls for the extraction of the information needed to resolve the integer ambiguity from the data collected while the kinematic survey is in progress. The second addresses the use of the antenna exchange technique for mobile platforms where the original locations of the antennas are not likely to remain stationary during the physical exchange. Both ideas count on information from additional measurements to augment their respective measurement models.<>