Simulation Research on Feasibility of the Shipborne Pseudolite for GPS Augmentation

In allusion to the need of high-precision and high-stability navigation system in the airplane during taking off and landing process, a original shipborne pseudolite for augmenting GPS has been put forward. The feasibility of shipborne mobile pseudolite has been analyzed by comparing with the airborne pseudolite, and the performance of shipborne pseudolite is superiority over one of airborne pseudolite´s. Geometric Dilution of precision (GDOP) is deduced from the pseudo-distance error, it is approved that GDOP can be reduced by using shipborne pseudolite and the difficulty of GPS receiver select satellites is debased, the select satellites method which calculated the maximum volume of four GPS projected tetrahedron is simplified to calculated the maximum area of three GPS projected triangle. By the way of simulation, the variable trend is analyzed quantificationally between GPS augmentation back and forth, while GPS vertical angle varies from 0deg to 70deg and pseudolite vertical angle varies from -15deg to -90deg, the navigation system has a optimum performance.