INS Aided GPS Integer Ambiguity Resolution

Real-time high precision GPS positioning is based on carrier phase measurements, which requires fast and precise on-the-fly integer ambiguity resolution. In some navigation applications, external sensors are available that provide auxiliary measurements. For example, in GPS/INS navigation systems, the inertial sensors allow computation of prior position estimates when GPS signals become available. This information can be used to aid GPS integer ambiguity resolution, offering a higher probability of obtaining correct integers, especially in challenging GPS conditions (e.g., few satellites, high measurement noise). This paper describes a fast and efficient technique for integer ambiguity resolution when auxiliary information from INS is available. The theoretical derivation will be presented and simulation result will show the effectiveness of the proposed method.